Transmit 3.6.6 has been posted to our web site.
Shortly after releasing 3.6.5 last week, we discovered that TransmitSync (a helper application for syncing Transmit favorites over .Mac) was crashing under certain configurations and circumstances. (You would receive a "TransmitSync has unexpectedly quit" dialog if affected.) This is fixed in 3.6.6
The only other change in 3.6.6 is the restriction on usage of dot characters in a new Amazon bucket name that was added in 3.6.5 has been removed. You are still subject to Amazon S3's bucket naming rules, but we now leave most of the validation of dot characters up to Amazon.
Transmit 3.6.6 is a free download for all Transmit 3 owners.