It's the Glicko system which tries to quickly establish your rating by rather large swings in the beginning. After you've played a few dozen games the swings become less. There's something called a Rating Deviation that is key to this. The higher the RD, the larger the swings. Lot of previous threads on this:
http://www.chess.com/forum/search?keyword=Glicko+RD
Could one of the wiser of you inform me as to the rating system here..Is it Elo or similar? and if different what is the difference? And how much does a win over someone with 100 points get you...etc..
thanks a lot...
Mr "Needs to get better faster"