IsEnabled or Enabled

I actually got a chance to write a little WinFX code today, which was a lot of fun. But I did run across one issue that has been in the back of my mind for while. It is the “Is” prefix on Boolean properties.

I started out by using the WinForms Timer class (which, BTW doesn’t work in Avalon because it is tied to the message bump).

myTimer.Enabled = true;

When I found my bug I moved to using the Avalon UITimer class which worked like a charm except I needed to change to using:

myTimer.IsEnabled = true;

What do folks think is the IsXxx prefix worth the break from the WinForms model?