Dammit - I can't find it now, I did a quick search and I cut out some articles recently.
There have been reported cases of Guillain-barre syndrome which is an auto immune disease. Most patients recover, and the paralysis can be severe.
I also noted that the GBS also came under the spotlight in 1976 when people were vaccinated against swine flu.

I'm in the middle of a work crap storm right now, I will find the info for you. There is plenty on google about how great it is, you will find a paragraph here and there about the side effects, they are now saying it is safer to stay at the dr's for 15 mins after the vacc.
I developed GBS after receiving my annual flu shot when I was 10 (in 1992), I was fully immunised already (as I'm a brittle asthmatic). Recovered fully from the GBS, but the specialist who treated me and my GP gave Mum and Dad a list of vaccines to avoid in case I developed it again.

I asked my GP about the HPV shots and he didn't have a definite answer, but he didn't want me to get them. If I went back and talked to him again now, a year later, he might be able to elaborate further on his not wanting me to get the shots.