Although Apple does not list DVD-RW disc support for the OEM Superdrive (and does not support DVD-RWs in iDVD or DVD Studio Pro currently), Pioneer does list DVD-RW disc compatibility with the drive. (Past reader reports have noted using DVD-RW disks and Toast 5 also notes support for DVD-RW as well as the write-once DVD-R discs.) A reader noted in the forums that OS X 10.1's Disc Utility appears to also offer support for DVD-RWs (including erase options):

" I also have a DP 800 and the Superdrive firmware 1.49. I haven't tried it yet, but MacOS X 10.1's built-in disk burner recognized a Pioneer v1.1 DVD-RW as a viable blank, and Disk Utility gives an option to erase this disk... So with 10.1, Toast isn't needed to burn data DVD-RW.
Cadaver

(Update) Several readers replied to this post noting they'd used DVD-RWs. The details page lists two of the most detailed reports received this morning.

" I was the one posted the info about the DVD-RWs in the forums...
I did some testing last night and this morning, and here's what I've found.
Data DVD-RWs can be burned directly from the Finder in 10.1. A backup DVD-RW I made with a little over 3GB of data was also perfectly readable in my Pismo PowerBook's DVD-ROM drive (just FYI, the PowerBook has an LG mechanism. I'll try it later in a different machine).

OS X 10.1's Disk Utility will erase DVD-RWs with no problems at all. Interestingly, the progress bar while erasing runs backwards... a cute UI touch from the Apple folk.

DVD-RW burning, at least via the Finder, is pretty slow, though I don't think it's Apple fault.
[Note - Pioneer notes 1x DVD-RW speeds, but 2x DVD-R Speeds. DVD 1x speeds are 1,380KBytes/sec, not the same as CD 1x rates which are 150KB/sec.-Mike]
The actual data writing goes relatively quickly, but it takes a long time to "finish" the disk once all the data is written. It takes, what, 30 seconds to a minute for a CD-RW to "finish", so I guess this takes all that much longer given the data capacity. I have not tried burning any data DVD-Rs yet to see if it's faster on non-rerecordable media.

One note, DVD-R & RW disks from the Finder can only be formated as 4.2GB HFS+ disks, which means they probably won't mount in a PC's DVD-ROM drive. But, as I said above, a DVD-RW data disk was perfectly readable in my PowerBooks's DVD-ROM drive.
[Note: Pioneer's Superdrive manual notes that the 4.7GB disks "equates to 4.37GB of recordable data". They note this is due to the same reason why a 20GB, etc. Hard Drive actually has less formatted capacity reported by the computer - primarily the decimal vs. binary (computer) numbering system (noted in the FAQ here for years). For example 1GB in decimal (base 10) is 1,000,000,000 bytes, in computer (base2) 1GB = 1,073,741,824 bytes.-Mike]
All tests were done using Pioneer DVD-RW 4.7GB version 1.1 media. SuperDrive has v1.49 firmware. "

" Hi Mike,
Just a quick note to let you know I have successfully written data to a Pioneer DVD-RW (Ver. 1.1) disk using OS X 10.1 and Disk Burner. I was able to format the disk using the Apple Disk Utility. I have done this repeatedly now and am satisfied that it is working correctly. The drive is a Pioneer DVR-A03 (DVR-103 as reported by Apple System Profiler) with firmware version 1.44. I have it installed in a Dual 533 digital audio G4 with 1.2Gb RAM, 2x 60GB 7200RPM Maxtor drives, and an internal Zip 250 atapi on the same bus as the DVD-R.

When I visited the Tyson's Corner Apple Store I checked the Superdrives and found that they had version 1.49 firmware installed. Pioneer's website lists 1.55 (The 1.55 firmware updater needs to be run from DOS) as the latest firmware for the A03 but they caution against using it on an OEM drive. However, I would prefer to install the Apple firmware (v1.49) on my A03. I doubt Apple will ever make it available for a non-OEM drive. The information at the Pioneer site lists information about the A03 and 103 drives but is very obscure about the differences between them. Apparently Pioneer does not want people to update the drivers on the OEM equipment using their firmware, which would be foolish for obvious reasons. The Apple system obviously recognizes the A03 as a Superdrive (103) in every way. Disk Burner, and iDVD work just fine with it. I just hope iDVD 2 works.

I have 2 annoying problems though. With Mac OS X 10.1 the F12 key functions as a media eject key. Great for those without pro keyboards but very annoying for me since I tend to hit it when I go for the delete key. I have not found a way to turn it off. Also, I have 5 old FUJI CD-RW disks that I have formatted with Disk Utility and with Toast preview 2. I was repeatedly able to format and burn one of the disks with Toast and with Disk Burner. The other four repeatedly fail to write with either. I can format the disks but the disks fail the verification process in Disk Burner with an unexpected error (error code 6).
Best Regards,
Fred Argilan"

I've had some reports in the past that even the retail Pioneer DVR-A03 (per the manual, etc.) was actually reported (in Apple System Profiler or the PC's Windows Device Manager) as a "DVR-103". Makes me wonder how many A03 models they actually shipped. I can verify that the OEM superdrives cannot be flashed on a PC with the Pioneer 1.55 firmware update (a kernel error is reported in DOS during the attempt.)

Reading DVD-RW Discs: Not all DVD ROM drives can read DVD-RW disks. Here's one reader's comments about his PowerBook G3 2000 (Firewire model):

" Mike-
I've written a couple of emails and posts recently regarding my DVD-RW experiences... I discovered this today, and thought you would like to know- While the data DVD-RW I created mounts just fine in my Pismo, it apparently doesn't work in all of them.
I have access to two Firewire PowerBook G3 machines, both 400MHz models, both running OS X 10.1, and after swapping DVD drive modules around, it seems that a Matshita SR-8174 mechanism in an older Pismo will NOT mount the DVD-RW at all (no matter which machine the drive itself is in). The read head thrashes around a bit, then seems to give up. The disk never mounts. The LAB8 DRN8080B (as labeled by Apple System Profiler - is this an LG mechanism?) in a newer Pismo WILL mount and read the DVD-RW just fine. The LAB8 mechanism is from a Pismo bought shortly before they were discontinued. The Matshita mechanism is from a Pismo bought just after they were originally released.
Thanks for the site!
Michael S. "

My wallstreet DVDROM drive won't even read some CDRW discs (seems worse with some dye colors). I'm not sure if Apple has any firmware updates for the pismo DVD drives to address this but there have been iMac and Cube DVD ROM drive firmware updates, as well as one for the PowerBook G4. (These updates were to address other issues, DVD-RW ws not mentioned in them that I remember.)

On a related note, I just burned a DVD-R disk last night - but my older (2 years old) Toshiba home DVD player will not read them. It has some issues with certain dvd titles also (at least with xmen - doesn't get past the menu - starting the movie grinds and grinds...) A reader once told me you can send it to a Toshiba repair facility (at your expense) and they will update the rom to address this, but never called them to inquire about that.

Other OS X 10.1 Articles:

• OS X 10.1 vs 10.0.4 performance tests (comparing performance in both versions plus classic, apps and games, drive tests, and more)
• OS X 10.1 First Impressions (DVD player, CDRW burning, disk utility, screenshots and more)
• Optimizing 10.1 with SpeedDisk
• OS X 10.1 and Firewire Drive Mouting/Sleep Tests