Macbook pro 13 2011 feels slow

Hi everyone, I have a MBP 2011 Lion upgraded to 8GB ram and upgraded to 120GB vertex 3 Solid State HD and internal 500GB apple HD that it came with. When I first boot the laptop top everything is fine but as the day progresses the thing feels slower and slower. I can really feel this in safari. The two finger scrolling becomes choppy and pages tend to load much slower. The cure of course is to reboot and everything is fine again. Could Lion be causing this because i dont remember snow leapard doing this before? I have Google Chrome and FIrefox and they both feel the same as Safari. I am not really running anything in the background. I have pleny of storage left on the SS (35GB). I run activity monitor and everything is behaving normal. Plenty of ram. I run frozen flash so no unnessesary flash programs are running. Any help would be appreciated.