I have MobileMe set up similarly. I have my Google Apps email forwarded to MobileMe. In the settings, I also changed the SMTP server to use the Google Apps server (which is the same as the Gmail server), so that emails I reply to will send from my Apps address. However, this is my work account, and not the account I use most, and therefore, I have another email account set up as the default. MobileMe still pushes to me fine. I find that email hits me within 5-10 seconds after sending. I don't think the default email account setting affects how MobileMe works.
Originally Posted by CrackBerry Kevin
Oh yah, one other thing. I also have the Apps account turned off and I also set my Apps account so that every email that is forwarded is automatically marked read. It keeps the inbox cleaner and I don't look at the same email twice.