The Slashdot thread which Adina linked to above has information that would have put many people's minds at ease, had the information been posted on Seagate's site at the beginning. Great link, Adina.
Information is woefully sparse regarding non-Windows and non-Intel Mac solutions. Many of us have Intel portable Macs with these drives as externals, and pre-Intel PowerMacs with them internally. I find no info regarding the flashing of them via eSATA, etc. It seems the company is still reeling and can't quite come to the point of writing a simple, informative, succinct article to cover several likely scenarios. I'm glad I'm not working in that environment.
My four or so "affected" drives are working fine for now. I'll copy over to new non-Seagate drives tomorrow and keep using the drives as usual until the path is clear and reliable. I'm happy to diversify my set of drives anyway.