.Net Framework vNext 4.5.2:
Now you can download the .Net Framework 4.5.2 (also known as .Net Framework vNext), a highly compatible, in-place update to the .NET 4.x family (.NET 4, 4.5, and 4.5.1). It gives you the benefits of the greater stability, reliability, security and performance without any action beyond installing the .NET 4.5.2 update i.e., there is no need to recompile your application to get these benefits. For more info, you can refer.

.Net Framework vNext

What’s there for Developers?
- Checkout the official announcement from blog post from DotNet team blog, where it tells that MS will continue to fully support .NET 4, .NET 4.5, .NET 4.5.1, and .NET 4.5.2 until January 12, 2016, this includes security updates as well as non-security technical support and hotfixes.
- Beginning January 12, 2016 only .NET Framework 4.5.2 will continue receiving technical support and security updates. There is no change to the support timelines for any other .NET Framework version, including .NET 3.5 SP1, which will continue to be supported for the duration of the operating system life cycle.
- For Application compatibility including .Net runtime and re-targeting changes across .Net versions, you can refer here. It’s a a great migration guide for the app developers – so check it out.

.Net Framework Support lifecycle:
You can have a look at the Microsoft Support Lifecycle site for .Net Framework.

.Net Framework 4.5.2 features:
For more info, about the new features in the .NET Framework 4.5.2, you can refer here.

Related Q&A:
Checkout the few interesting Q&A’s listed here. Adding a snapshot of my favorite.

.Net Framework vNext

Download:
You can download the following: .NET Framework 4.5.2 Web Installer | .NET Framework 4.5.2 Offline Installer |  .NET Framework 4.5.2 Language Packs | .NET Framework 4.5.2 Developer Pack.