If you are developing for WP7, you'll notice that edit and continue is not supported. That's a bit of a bummer, but it's far less annoying than the constant dialog that pops up to tell you that it's not enabled.
A two second trip into Tools->Options->Debugging|Edit and Continue to disable it will make the dialog go away. This lets you type in the editor while debugging in the emulator!
A two second trip into Tools->Options->Debugging|Edit and Continue to disable it will make the dialog go away. This lets you type in the editor while debugging in the emulator!