So I can return to my code, which I've completely forgotten how it works, see that it compiles, read it through, and continue working. Noticeably: I do not need to care about the tooling because it just works. I don't get a shiteload of weird exceptions when I run my code (looking at you, Clojure - yes, I'm a noob) and since the Pythonic and mutable nature of F# allows me to write code in the way I enjoy the most it feels like a glove. There are a few oddities occasionally and some bits are a bit more verbose than in other languages (Clojures collections spoil any other language) but the overall experience is that I can focus only on my code. For me, it's a pain free computational substrate, and free as in beer now that Visual Studio community edition is out.
My progress is really slow but always worthwhile.
If you are interested I found Jon Harrops "Visual F# 2010 for Technical Computing" really good practical introduction, Don Syme et. alls "Expert F#" a good reference book on writing general stuff in the .Net ecosystem with F#, Petricek's "Real-World Functional Programming" a very good introduction to various application patterns and Sestoft's "Programming Language Concepts" a great book and online reference on writing interpreters and compilers (http://www.itu.dk/people/sestoft/plc/).
*At work I use C++ on MS stack.
Table of contents and sample chapters here - http://manning.com/petricek2/
That said, I'm glad MSFT is now competing in the open source/x-platform desktop app space. The Java team can use the extra competition.
Unfortunately I have to love Clojure from afar. Partly because I only touch it for Riemann so I'm always rusty, and partly because the JVM. I'm really hoping that all this open source .NET business will bring more attention to ClojureCLR though. ClojureScript is a wonderful thing and I know there are some F# and CIL->JS transpilers but LightTable->ClojureScript->Chrome is a wonderful thing. A similar story, complete with insta-repl, with F# would be crazy cool.