I did a comparison between the bootup of snow leopard and lion, and theres like a 10-15 second difference between the 2, SL being faster. I read up on some sites that, benchmark wise, SL is faster, but it seems that the benchmarks just dont seem to like Lion very much. Would bootcamp slow down the boot time?
That was my experience too. After i upgraded ti Lion my MBP was slower and the battery did not last as long. It went from 7-8 hours to 5-6 hours. Activity monitor did not show anything out of the ordinary so I wiped the drive and reinstalled SL again. My battery and boot times went back to normal.