I suspect they injected the bug to force the upgrade. Remember, if it was just disabled, enterprising hackers would find a way to re-enable it. Burying in a 'randomly corrupt the data during writes' feature, and then disabling the device so innocent users don't get hit by it is much more effective.
My data is not corrupted and I manage to do daily backups to my AEBS + HDD. I have even restored from it, admittedly TM is a little sluggish sometimes reading from the drive, but it works. I suspect there are just little issues with each vendor and Apple realised this and went with a vendor that works best.
And once again, it seems likely that a fix would have to come from an Airport Extreme update, not an OS update.
I'm still hopeful it will come out, but I doubt you'll see it in 10.5.2.
Well here's an interesting thing. An HDD connected to an AEBS does not show up in Disk Utility, so how would you reformat a Time Capsule if something went wrong... taking it into Apple seems unlikely. Perhaps a firmware upgrade will come allowing Disk Utility to see the drive, among other things, and that'll change the status of backups.