For me, the best solution is based on iSid’s answer: to add an external tool that pops up the old dialog.
You can do this from Visual Studio: TOOLS -> External Tools… -> Add, with the following values:
Title: Checkin (or any name that should be displayed in the menu)
Command: C:\Program Files (x86)\Microsoft Visual Studio 11.0\Common7\IDE\TF.exe (this is the default VS install location on Windows x64)
Arguments: checkin
Initial directory: $(SolutionDir)
Here is a screenshot:
You can invoke from TOOLS -> Checkin (or even assign a keyboard shortcut to Tools.ExternalCommand* as described here) and enjoy the old goodies with a new style:
Note that this won’t work if a solution is not opened, because of the $(SolutionDir) variable. To workaround this, you can hard-code the path to your workspace instead.
Additionally, tf.exe can be invoked with ‘shelve’ argument, which will show the old-style shelving dialog.