Just for the record, I had three Firefox versions, 1.5.0.9, which I tried to remove, FF3.0a2 nightly, which was never installed, since I was working from the unzipped file. FF3.0a2 was listed in the Add/Remove, nevertheless. I had deleted 3.0a2, now removed from the Add/Remove since it was stealing default from FF2.0.0.1. Now, I am down to a more manageable single Firefox, and may install 3.0a2, if it behaves itself.
However, this experience has not been pleasant.
UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.1) Gecko/20061204 Firefox/2.0.0.1
