If you are a start-up or an established Independent Software Vendor, producing Microsoft products, take a look at this program.
It gives an easy (and cheap - currently £240/$375) way to partner with Microsoft, without certification or testing requirements up front. You get an MSDN universal subscription with 5 user licenses plus other benefits for a year. In return you commit to releasing a packaged product, running on MS technology within the year. Pretty good value if you are an established ISV anyway.