Several MacMinute readers in the U.K. report that their new iMac orders from the Apple Store have shipped. Supply remains very tight, however, and it’s unclear when resellers in the country can expect stock of the system. Updated 12:25 Craig Sanderson has informed us that PC World, a U.K. Mac reseller, had a few units of the new iMac in stock today, although a salesperson said supply is very constrained.