Personally, I think it is better to launch in less countries then more, especially if your competitor is not available in those countries either. If you launch in the other countries later, you are going to get those sales anyway. But like people have already pointed out, if you are out of stock, you risk losing a customer (and a sale) forever. Ideally, you should launch a week or two prior to your competitor to get that jump start, but that is probably all you need. In my opinion, launching a month or two earlier is not going to earn you loyalty or PR to sway customers from the competition.
I have a feeling that Sony did not expect to get the number of sales that they have, so they made launch plans globally. This way they could keep the factories turning out 2 million consoles monthly and keep adding territories to maintain demand.