That's what it's looking like. I'm not entirely sure why the Mozilla foundation even continued to develop & promote two major projects like this in the first place. Maybe if they weren't so similar, but with the resounding success of Firefox, you had to know this was coming.

"Further discussion seems to indicate that with Firefox and Thunderbird development, along with other Mozilla Foundation activities, and the lack of developers, reviewers, and sufficient users of the Suite, there very well may not be a final release of the 1.8 version of Seamonkey."