For the longest time, I always thought MP was only good for 2 albums on any side-projects: LTE only did two (well, because JR joined DT, and their reasoning for not doing LTE 3 was solid at the time), Mike only stuck around for 2 OSI albums (though that was due to tensions with Kevin), and at the time of Neal's leaving TA they had only done two albums. Mike has had some weird luck with doing just two and done in those instances, but at least Transatlantic has since reformed and done two more. I hope he does more with TWD, and at least Flying Colors with working on their third one already, so we're getting there.
Honestly, I've always felt that Neal Morse has been Mike's "main band". Sure, he doesn't have the same kind of control or input as he did in Dream Theater, but his work with Neal on hi solo albums has been so prolific that it's hard to separate Neal from Mike's career, especially since leaving Dream Theater. In the 6-7 years since he left, Mike has done 4 solo albums with Neal/the Neal Morse Band, as well as 1 with Transatlantic, and 2 with Flying Colors, not to mention a TON of touring. I see The Winery Dogs, and other things like Metal Allegiance, as ways of Mike to perform non-prog music, though i definitely do not see them as any attempt at creating a new "main band" for himself.
What awaits us for this new one though could be anything, and if it's a new main band for him, more power to him, but at this point in his life, starting a new band to put more focus on seems like a hard thing to do. How many more albums could he possibly do to make something like this prog-metal supergroup be a true success? How this first album is received will really affect whether or not Mike continues with it in terms of how much effort he'll put into it, just by looking at how successful TWD has been. Unless of course this is all just a passion project and he's not looking for success or fame or recognition - just a chance to write and perform the kind of music he used to play in Dream Theater.
-Marc.