I tired searching the site but couldn't find that anyone posted it, so I figured I would share this site with the community:
www.trueachievements.com
Basically it weights your achievement based on others that are being tracked and gives it a weight valued, so if a achievement is one that everyone gets, the ratio gives like 1.0 so 20 = 20, but if its a really hard one to get and not many people have gotten it, it might be rated like 2.5, so then your 20 turns into 50.
They have tons of stats too, like what your completion percentage is, your average ratio is, where you rank in the community, and you can set goals for when you want to get to a certain level.
The site scans your account like once or twice a day and pulls in what you have accomplished in the past day, AND it has this cool friends feed that shows you what your friends are getting.
Kind of cool I think, thought it might be interesting for achievement junkies out there. Gives some perspective on how hard some of these achievements really are.