It appears that AQ or some affiliated/sympathetic group has pulled off an attack in Qatar, and it threatening to blow up "crusader" military bases. Of course this threat could be b.s., but there are some implications here.
The biggest implication is that Qatar is one of few places in the Middle East where you can expect NOT to be blown up. Our troops are using one of the bases there as an R&R location from Iraq. Kinda hard to rest and relax if you're worried about getting attacked. I felt pretty safe in Qatar, but I'd have to wonder now. I'm sure that fit somewhere into the bad guy's plan.
Its also important to note that the suicide bomber is alleged to have been an Egyptian national. Estimates are hard to find, but the population of foreign workers is Qatar is very large. When I was there, we had Philipinoes, Pakistanis, North Africans, and Indians working on the camp. If you go into Doha, the feel is even more diverse.
But, this does not come without problems. Most of the "guest" workers in Qatar labor in the service industry or in the oil fields. They live in slum apartments on the edge of town, and I've read reports that they are often mistreated. These conditions are a breading ground for terrorism.
This blog out of Qatar has some things to say about the situation. There are pictures in the gallery page. Doha is not a very big city so I can imagine that everyone is feeling at least a little uneasy right now.Her blog notes something interesting: "Only last week I was in a cab and the driver was listening to a speech encouraging people to go to Jihad across the globe. The preacher highlighted specific areas: Iraq, Palestine, Chechnya and Kashmir. The driver didn't seem to be bothered by what he was hearing, he just sat quietly absorbing it all. The two of us listened to that speech in the cab from my house to work. It was still going when I got out."