Hide 'On my iPhone' calendar when syncing with MobileMe Ive now switched back over to MobileMe for all of my calendar stuff. 

I was wondering though, if I go to 'Calendars', it also displays a calendar 'On My iPhone'. I don't think I would ever want to use it (because I want it to write to one of my two MobileMe Calendars). 

Is there any way to remove this other calendar? Or at least make it so its not the 'default' one? Even if I tell the iPhone to not show it - it still wants to write to that calendar by default
Yes, I think you can change this settings in iCal, as your mobile me settings are in there.  I did this, and my iPhone only shows my Mobile me calendars.  

If you use gmail, I would also reccomend BusySync. It syncs anything you add to you iCal, and then iCal and mobile me syncs.  Its pure awesomeness in my opinion.  

Also, if you have devleoper tools enabled, you can edit the plist mobileme sync-time interval to 1 min, instead of 15.  You can access the mobile me plist file in home/library/preferences/byhost/ - the specific file name is like: com.apple.mobilemesync.. or something like that.  Im at work, and use a linux system, so if someone else knows, please confirm, otherwise i will update this when i get home.