Was contacted by a recruiter in late July after submitting my resume to Microsoft online several months prior. I had a phone interview scheduled for early August. This phone interview was a half hour long, and while it was with an HR person she did as a few technical questions, such as how to quickly find the middle element of a linked list. She also asked about how I would go about testing a vending machine.
In another 2 weeks I was invited to interview in Redmond in late September for a SDET position. Microsoft booked my flight, hotel for 2 nights, and rental car. On the interview day, I was there with 7 other SDET candidates. We had lunch, and then a series of 4 interviews that lasted 45 minutes each with 15 minute breaks in between. Each interview was with a Test Manager, and each one consisted of a few minutes of talking about my resume and then some technical questions. After all the interviews were over, we were free to go for the day, and they told us we'd know by the next day if we would be getting an offer. I had the evening free and went to Seattle to explore a bit. The next morning I got an email informing me I wouldn't be getting an offer.
Overall it was a difficult but exciting process (free trip to Seattle!). Microsoft will reimburse for most everything, so even if you're only slightly interested in the position, definitely take them up on the offer to interview.