This is an annual award that recognizes "exceptional technology community leaders worldwide who actively share their high quality, real world expertise with users and Microsoft." There are fewer that 4,000 awardees worldwide, so it's a select group of the best and brightest.
MVPs have the opportunity to meet Microsoft executives, participate in speaking engagements and customer events and get involved in technical content development. They also get early access to technology, keeping them on the cutting edge of the software and hardware industry.
Congratulations to Rob - we're looking forward to hearing about his MVP experience in the months to come.