So what's the catch?surely MS isn't giving you this for free??? Well, that was my first thought anyway... turns out that they actually give you this for almost zero... There is no obligation to continue to use any of the software after the three years is over, and there are no costs for the three years other than a $100 program fee at the end of the three years. If you want to continue using all the great stuff, you can do that at a charge of $999/year package, or you can only buy the productions server licenses for $199/year (web and database server).
The other good news is that you can upgrade the tooling, for example VS2008 to VS2010. And not to mention the free publicity you get!