Only announced in September, Microsoft has kept true to their word and released the Visual Basic programming to for Windows Phone 7, allowing an even larger number of developers to jump in on the platform.
Using these tools, developers can now have multiple means to writing code for WP7 and even more importantly, can start today. One limitation though is developers can only use it for writing Silverlight apps, not XNA, meaning games are out for now.
Kudos to Microsoft though for bringing "the most requested" tools to developers in 60 days. Hopefully we'll even see more quality apps as we near the 3,000 mark this week.
Source: The Windows Phone Developer Blog