They're recommending that expectant women get the swine flu vaccine because it's hitting young people (particularly 20 and 30 year olds) so hard. There was a pregnant woman in Chicago who died last spring from the swine flu, and the baby was too young to even be delivered. The autism concern is due to the thimerosal used to preserve many of the vaccines and getting the shots as babies, but this doesn't apply to fetuses. It's a danger to the fetus when mom gets a fever above 101 F regardless of the reason (flu, bacterial infection, etc), and this flu is causing people to get fevers in the 103F range, another good reason for pregnant women to get the shot.
Barring any other health issues that any pregnant woman might have, it seems to me the benefits of getting the swine flu/H1N1 shot (not getting sick with a flu that can kill a young person, not getting a fever so high it can cause damage to the baby) outweigh the risks. I have a contact allergy to thimerosal (a preservative in many flu shots), and if I were pregnant I might take an anti-allergy med in order to take the swine flu shot to decrease the risk of high fever. I would urge all pregnant women to discuss this issue and their concerns/specific health issues with their OB/midwife as soon as possible. I'm a big proponent of limiting medications to the minimum necessary during pregnancy, but if I were pregnant the H1N1 shot would be on my list of shots to get. There has been a lot of testing done on the shot in the US and around the world, so I'm comfortable with it in this situation.