I confess that I really like Expression Web. It doesn't do everything I'd like, and it doesn't magically solve all my CSS mysteries (and believe me, I create more than my fair share of CSS mysteries) but it gives me a whole lot more options than I'm used to when it comes to designing sites. I also like the built in templates and CSS layouts (though I'd like to have the option to create a website based on master pages to save me the trouble of "converting" it when I want to use it in ASP.NET).
Anyway, I was asked last night about source control integration in Expression Web. Does it have it? Will it have it. The answers are "not in this version" and "it's on our radar". In other words, it's being considered for v.next (or v.next++).