I'm tempted to label as "shocking" the announcement that F# will become a product fully integrated into Visual Studio, but I suppose it would be hard for anyone to ignore stuff as compelling as this.

F# is a derivative of OCaml and is a functional programming language. Those who delve into my language-related or concurrency-related posts will be familiar with the concept that one of the great advantages of functional languages are characteristics that lend themselves to automatic parallelization. Microsoft is making more and more noise about functional approaches (Eric Lippert's "aside" that "Immutable data structures are the way of the future in C#." is telling.) and this endorsement of F# is another sign that Redmond is throwing its weight pretty heavily behind this approach.

F# has been well-received among the hardcore language nerds but you have to give Microsoft credit for getting out ahead of the market on this one. F# is a very different beast than the Iron* languages (Python and Ruby). This isn't Microsoft reacting to market demands, it's Microsoft putting a not-at-all-well-known language into the spotlight.