An update to ASP.NET is due to be released early next year. If you are eager for its new features the Release Candidate is now available for download.
ASP.NET and Web Tools 2012.2 is described as as tooling refresh of Visual Studio 2012 that extends the existing run time with new features without breaking existing applications.
This new features include:
Web Application and Website project publish experience now have a unified publish experience and selective publishing options have been added.
New Web API functionality including support for OData, tracing and generating a help page for your API.
New MVC templates for Facebook apps and Single Page Applications.
Real-time communication via SignalR.
Extensionless Web Forms via ASP.NET Friendly URLs which makes it easy for web forms developers to generate clean URLs without the .aspx extension.
Editor support for Knockout IntelliSense and pasting JSON as a class.
In his blog post announcing the release candidate, Scott Hanselman explains the status of ASP.NET and Web Tools 2012.2:
Why isn't this called ASP.NET 4.6? Because it's not. The GAC'ed ASP.NET 4.5 doesn't change. This is mostly a tooling update as well as a collection of NuGet-based libraries that augment but don't replace ASP.NET 4.5. If we called if ASP.NET 4.6 then folks would think they needed to rush to update their servers. They don't. It's an update for "Web Tools for VS 2012" but that's lame, so since we got the VS guys to use the .1, .2, .3 scheme rather than September Update CTP Refresh, then we can make things easier by calling this Web Tools 2012.2.
He has a lot more to say about the release in this hour-long video that was presented at BUILD. Note, however, that this presentation relates to an earlier version and also predates the latest name: