We skipped VS2013 / .NET 4.5 and jumped straight over to VS 2013 / .NET 4.5.1 because, y'know, it's far more exciting running your production servers on beta software rather than on the boring "tested" stuff.
We're not using any of the fun stuff explicitly, yet, but Matthew has already been eyeing off a bunch of code that can do with some async action. The thing that's most immediate to me is the multi-core JIT and startup time; all cores are actually getting used, CPU usage is up where it should be, and the site spools up much, much nicer than it ever has. Simply getting the advantages of the framework improvements is (almost) enough for me.
The other obvious timesaver is build time: much, much faster than VS2010, even when bogged down with all the other stuff I have open. I'm developing, testing, and running the site on my Macbook Air on Win7. There's the VS IDE, SQL Server Management Studio, IIS running the actual site, Outlook groaning under the weight of a 23Gb pst, various Word docs and spreadsheets, 6 remote desktop windows and half a dozen browser windows and it's all humming along nicely.
Although sometimes (especially during compile time) the humming sounds suspiciously like the Mac's fan is about to attempt takeoff. It gets disturbingly loud.
I'm still not taken with the new VS look - a little harsh, a little lacking on warmth, but it's way faster and, so far, more stable than my old creaking install of VS2010.
As to my experiment with moving my developer life onto a tiny, ultralight laptop: the jury's still out. 7/10 so far.
I got sick of typing URLs for members and so, well, I coded.
To provide a link to another member just use the tried and true @username syntax, where the username is the username generated from their name (or manually modified) in the form first-last. Everyone's profile shows the username just under their profile image.
So if I want to shout out to a ray of sunshine I can just go @Michael-Martin (no link - just type that literally) and when the message is saved the link is generated.
Obviously this is opening a can of worms and I know the next two requests. Yes, soon.