I'm currently sitting in with the team behind iTraveller.com.au, a WPF application that is being shipped locally here this week. It's down to the last hour(s) so to speak and everyone is tired, over worked, stressed and have taken Expression Blend (May Preview), Orcas and XAML out for a nice hard run.
Problems the team faced are stupid stuff, that we (Microsoft) are hopefully going to fix, and it's nothing over the top in terms of concerning, just small annoyances here and there. Example would be that when you are in Expression Blend, you double click on the XAML tab (Design to XAML), one would expect that the XAML pad would go full screen, negating the need for panels and so forth to be visible (as the Tool doesn't understand you are eding the current node item at the given time). It doesn't, it just stares blankly at you like you're some kind of ass whom is a bit slow on the uptake. Not to worry, I've got a list of these little annoyances an arm long and will shoot them through to the internals as constructive feedback.
One thing I will say though, is that when working with a team of developers at present, not having Visual Source Safe extension(s) in place is quite obviously hard and annoying, as each designer gets to play around inside WPF / XAML quite happily enough. Yet, when it comes time to throw their Resource Dictionaries or individual XAML pieces into the main pile, well this is where it gets interesting very quickly.
To combat that, the architect behind this project opted for Tortoise SVN, something I've used in the past for many years. It works a treat, but the catch is that one person has to own the .sln & .csproj files or kind of be the gatekeeper in the very least.
There are a lot of ways we could counteract this with some smarts in the room, but overall that requires time and these folks have managed to build a 6 month project in under 6 weeks (which is a testament to WPF and the Tools that support it).
There are some more interesting things I've managed to uncover from this project and once it's launched i'll sit down with the developers for a debrief and get their raw (unprompted) thoughts around it all. The entire project has had video diaries through out, so expect to see some footage of how it went from concepts drawn on "napkins" through to living breathing WPF based 3D goodness mixed with Meegos and Web 2.0.
I can't say enough positive things about this project at the moment and i'm looking forward to showing it to one and all once it's launched (mid next week).