1. Likely an AQ directed operation with classic timed, coordinated, multiple attacks.
2. It is not certain yet if these were coordinated via Al-Zarqawi in Iraq. Z has promised to spread his terror influence to allies in Europe. In a recent communication to OBL, Z allegedly refers to the initiation of some kind of operation and wants OBL's approval to proceed. If Z has coordinated these attacks, then his influence as the defacto operational leader of AQ has been secured and OBL has become more of a figure head.
3. This is the second attack upon a metro-rail system. This indicated a change in prefered targets. Apparently the choice of this target was bolstered by the success of the attacks in Spain last year. It produces high casualities and terror while the target enviromnent provides concealment to the bombers. This shift in tactics away from car bombs to trains suggests that this may be the method used in a future attack here in the US and Europe.
Well, with this and Madrid I think it is safe to assume public transit is a top target. 9/11 used our transit system against us as well. While I DOUBT we will be attacked in the short-term, it is worth raising our vigilence (I mean, we should have already - right?). The thing with transit though, it is very meshed with our economy. Hit buses, trains, planes, etc.... life can come to a halt. Their main objective (as UBL and Zawahri have said repeatedly) is to ruin our economy so that they may have an easier time hitting us in the future.
It could be that AQ wants to divert everyone's attention to the rail system then while everyone's focused subways, etc., they go for their big-ticket targets (i.e., malls, landmarks, maybe even N-plants).
ExSoldier checking in from north Florida on a dial up connection and a primitive computer and still on vacation....but this is my take on the above: According to the MSM in UK today, that stiff upper lip of the British is prominent. Ridership on the tube seems to be slightly off, but most folks seem to be taking a long weekend. I think it may bee business as usual on Monday. If that's so, then the desired effect may not be so great. True it's possible that the UK is a bit used to bombs since the IRA seems to set them off at times and the typical American sheep may bleat a bit more stridently! But it seems to me that it's got to be bigger than 911 or at least far more widespread. Comments on this (no pun intended) train of thought?