Looks like even Apple was caught off-guard a bit by how popular the iPad has been since the launch in the US, as the company announced earlier this morning that the international launch of the device has been delayed by a month. Apple says that more than 500,000 iPads have been sold in the first week of availability in the US, and to keep up with demand, Europe will now see the iPad in May, rather than the “late April” that was previously announced.