I'm now officially certifiable ... erm, I mean certified having passed my first exam:
070-315 Developing and Implementing Web Applications with Microsoft Visual C# .NET and Microsoft Visual Studio .NET
I now have 2 more to do to get MCAD status (MS Certified Application Developer) and 4 more for MCSD (MS Certified Soution Developer). If I get MCSD before Sep 30 I get a special "Early Achiever Certificate" which makes it a bit more valuable.
They should help me with work, especially when moving (just gives your CV / Resume that 'edge') and typically the rates for certified people are higher (some companies insist on only hiring certified staff)
... the only downside is that they are £100 a pop to take each test (incentive itself not to fail) plus a fair whack for books and training materials - and the later exams look HARD !