I love Orcas. I would say that of course, but for me personally I've been involved in so much of the blood, sweat and tears (yes - tears) that went into our features (debugging, profiling, code coverage) that it's great to see it finally be broadly available in the recently announced Beta2.
Soma created a blog entry recently on our features - see it here: http://blogs.msdn.com/somasegar/archive/2007/09/14/debugging-and-profiling-features-in-vs-2008.aspx
I kinda miss the hunt the thread game mentioned in that article. My highscore was 23. That and the fact that I actually wrote a version of the hotpath feature for V1 that got abandoned :(. Being able to drill down fast in the calltree view to the major bottlenecks is something that needed almost as much hand-eye co-ordination as "Hunt the Thread" (I wonder if I can TM that game).
It's amazing the amount of time that we put into the "infrastructure" this time around too. Things like Vista UAC support, WCF support, WPF support, LINQ support and x64 profiling suck up a lot of time to "just keep features working", especially in an area such as diagnostics where you are that bit closer to the metal (platform). So please, give the tools a spin on all of these areas and technologies. Have fun.