This past month or two have been really busy for me, preparing for the PDC in all sorts of different ways.  But I finally, finally got a chance to respond to some of the great questions and comments you've been sending in.  Most of them I replied by e-mail, but there's a couple I didn't have addresses for or wanted to share more broadly:

Judah asked, "I have read previously that WinFX API can make direct system calls, bypassing Win32 if/when necessary. Is that still true?"  I need to define my terms more precisely here.  WinFx = CLR + WPF + indigo (WCF) + Windows Forms + other stuff.  The non-WPF parts of WinFx don't get to call private APIs in Win32k.sys (the kernel-mode component of USER & GDI).  Not that they really want to, undocumented APIs are, well, undocumented, as well as fragile, poorly tested, difficult to use, and most importantly, are rarely necessary in a platform as mature as Win32.  For all those reasons, in WPF we've tried very hard to stick to the public APIs.  But in a few places, because we are part of Windows and bringing new power to the platform to, we do take advantage of private APIs created specifically for WPF -- primarily around the desktop window manager (DWM).

John asked, "Is there someplace we can look to get a concise view of what you get with WinFX that you won't get with Win32?"  I asked around, thinking surely we must have such a write up, but apparently not -- http://msdn.microsoft.com/windowsvista contains a little bit of information, and http://msdn.microsoft.com/netframework/technologyinfo/evalguide/default.aspx contains a lot about winfx in general but not much about Avalon in particular. Good news is that the upcoming Professional Developers Conference (http://msdn.microsoft.com/events/pdc/) in September is really geared towards exactly that sort of question.

Johan asked whether there's any other good blogs on WPF.  Tim & Karsten have put together a list of Microsofties blogging about WPF:

If you have any other good WPF-related blogs, particularly ones written by non-Microsoft people, I'd love to hear about it.  After I met Yves Dolce the other day, I came to the sad realization that I know most of the ~30 people on my blog reading list...  I mean, I like them and all, but I find it hard to believe I know all the interesting bloggers in the world.  <g>