As Steve notes on his big post:
Visual Studio Project and Solution Version Compatibility - .NETicated,
"Microsoft is saying though that they listen to Connect votes. Today Kathleen Dollard created a Connect item for this issue, and I encourage you to vote. It’s important. It matters. And Microsoft says they take action based on Connect votes."
"And remember, by not voting, you’re telling Microsoft this is not an important issue."
The link site is here