I've tried to use membership several times and its not flexible or usable. How about a simple model that calls evens (OnSignup , OnLogin, OnLoginfailed etc) so that it can pluf into existing applications easily

Allow complex project to follow domain driven constraint entity, value object, aggregates....

Add significant TypeScript support if MS is serious about it. A nice start would be "Paste JSON as TypeScript Class/Interface"

Whenever we are getting some error[the error types can be classified ] while debugging,VS should provision with a single button named as "Google it" or "Bing it" against the error..so that user can directly click the button and see the results against that error in search engine instead of going to the search engine and type/paste the error and press enter.It will save developer time and improve productivity.

I like to unit test a lot of my code, but hate mocking HttpContextBase just do to the horror of using something like Moq. It would be great to have a part of ASP.Net that was dedicated to unit testing and had built it classes that made it super simple to create mocks without heavy setup in my tests.

Also just make everything virtual in ASP.Net so we can override any public behavior (maybe not as possible).

The ability to do Russian Doll Caching like you can in Rails.

When deploying a site, the previous version should continue to run. If the deployment fails, the site should continue to run on the previous version. If it succeeds, the switch should happen after publication is complete.

common and cool controls where it's really easy to use such as http://awesome.codeplex.com and report viewer control for asp.net mvc

Allow Web.Config transforms to be applied to a deployment package without a rebuild under a different configuration.
QA packages can then be converted to production release packages without fear of introducing any subsequent changes.
Add ins exist but would prefer to have built in support

It's good to add XML comments to methods and classes. Especially for intellisence reasons but while reading a piece of code I think it's waste of screen space. Makes it harder to navigate the code. It would be great if I had the opportunity to have it always collapsed. Maybe with a symbol next to the method where I can hover the comment.

Same goes for attributes. I want to see that there are some, but not the details.

Code-First can run into some serious performance issues with LazyLoading. I would like to see Code-First (and its lazy loading feature) as a viable option for developing high performance web applications.

In VB, if you have the line IF A = B THEN C = D and the line is split after THEN the C=D statement should be contained between the IF and the END IF

Desired result:
IF A = B THEN
C = D
END IF

Current result VS2012:
IF A = B THEN
END IF
C = D

while knockoutjs is a nice databinding library, angularjs is a framework providing ioc and html extensibilty in a way the standart html dom will look alike in future standarts. intellisense support for directives and services would be cool.

Good or bad, there are times that I have JavaScript that does something to the effect: alert("Invalid Form Fields"). Bad example I know..but I have text scattered throughout my JavaScript files.

Where should these be abstracted to? Is there a reall cool pattern or method I don't know about? Resource files that gets rendered as some JavaScript object that contains all strings?

Need to have tools that gives interface like an app on tablet. Need something that connects asynchronous to server and give the users a rich experience like an win app or something like that. The 3rd party tools can be adopted to next framework as well.

For example, you could add modifiers specifying that a method only compiles if the generic arguments do not implement iEnumerable