Early last week I successfully passed the 70-541 : TS: Microsoft Windows SharePoint Services 3.0 - Application Development test!
I did extremely well on it so I am quite happy with my performance.
I am the first one to pass the test in my company, Perficient. Perficient-Philiadelphia is trying to get its Information Worker Solutions Competency - Portals & Collaboration Specialization. To get this, 4 people in our company have to pass the same test, so we can cross 1 off that list!
Contact me if you want to know more about the test and what it covers. I'll help you as best I can prepare for the test.
Check out the Preparation Guide for Exam 70-541
on Microsoft's site. They don't lie about what the test covers. If you know content in the areas it specifies that it covers, you should do fine.
Now that I've passed the test, I'm hoping to get on some more Sharepoint projects and really expand my knowledge and experience with Sharepoint.