@John Broughton -- I agree that we should probably think harder about the name. I didn't realize that people might think of their User page as a "homepage" -- I've always just thought of it as my "User" or "profile" page. One interesting thing to consider is that whatever name we land on will need to be translated into many languages (starting with Czech, Korean, and Vietnamese), and so it will probably be most important to convey to translators the concept that we're trying to cover with the name of the page. I think that concept is, "This is a place to get started each time you open up Wikipedia to edit." I wonder if a straightforward name that would translate well would be something like, "Your work". We can ask our contacts in those communities what phrase they recommend.
Yes, we're definitely keeping our eye on SuggestBot -- the creator, @MWang (WMF), is actually one of our team members! What do you like (or dislike) about that model?
I think it's a good idea to make that homepage (for lack of a better term at the moment) optional for experienced editors, but defaulted to "off". That's what we did for the help panel, and it's allowed experienced editors to try it out, so they know what newcomers are seeing.
We are definitely starting to think about how we will notify newcomers that the homepage exists, and a welcome message on User Talk and a welcoming email are both good ways. Other ways we can think of include CentralNotice banners, links in the help panel, a link on Main Page, and a redirect when someone confirms their email address.