Windows Vista SP1- Not good?

Hi guys, i installed vista sp1 on my system and since then it has slowed down a lot. and the applications i run are getting delayed in execution! :(

does anyone else facing this problem?

I searched and found this article : http://windowsconnected.com/blogs/aubrey/archive/2008/02/22/windows-vista-sp1-initial-thoughts.aspx 

it seems to be more like my situation!

currently am on XP, should i re-install vista without sp1 or roll-back?