Maybe your RC chrashes because of the "well known" Intellisense issue? http://weblogs.asp.net/scottgu/archive/2010/02/15/patch-for-vs-2010-rc-intellisense-crash-issue-now-available.aspx
I've yet to get my RC to chrash. It seems to be quite stable here.
I always am bemused to see these two words everytime a new version of development software is released: "breaking changes".
An incentive to keep your code as mainstream as possible, and an incentive for programming book writers too?