My understanding is that, like the annual flu vax, the swine flu vax is based on the virus that has already been around and it will only provide limited (if any) protection against the new strains that develop. I am not an immunologist (or any kind of octor ) however, so please don't take my words as gospel!

I can't get the flu vax (due to developing Guillain Barre Syndrome after getting the shot when I was 10) and I'm a brittle asthmatic, and I've only had the flu once in 17 years of not getting vaccinated. It really is a personal decision with the swine flu shot. I'm not going to get it due to the before-mentioned reason, but I know pregnant women who have had it and they (and their babies) are fine

If you want good information, see if you can Google some peer-reviewed articles maybe?