now i am 98 / 53 and 1877 still not as good as i was then i was 94???
no idea at all.

Yeah i know where you are coming from, i was 247 at 78-18, i win another game and i drop (WTF?) to like, 500th. I think it goes by your latest win and loss streaks, which is probably why im seeing people with more wins than losses and is still ranked better than me

The rank system has nothing to do with the win/loss ratio.
It's based on a point system.
whoever has the most points is going to be ranked the highest.
Suppose two people fight and both have 100 pts
The loser will lose 5 pts, and the winner will gain 5 pts...because they are even.
Now suppose one person has 500 pts, and the other has 100 pts.
By the ranking system the person with 500pts is ranked higher, thus has the advantage. So if the personwith 500pts wins, he will only win 1pt because he is playing a much lower ranked person of only 100pts.
However, if the person with 100pts wins, then because they are ranked lower, and are at the disadvantage, they will win 100pts, and the person with 500pts will lose 100pts So the best way to get a higher rank is to win against someone with a higher rank than your own.
It has little/nothing to do with the Win/Loss Ratio.
The actual number of points that you win/lose will always vary per match, and I don't know the actual numbers, however, I do know that this is the same principal of point system that Need For Speed Underground 1 uses for online play on PC/PS2, and it shows how much you will win/lose. It may be on a differen scale though.
~CYD

Yeah, um, my advice to you both is; just chill, enjoy the game, and don't get too caught up in the numbers. Here's a little something I posted in a different forum about a month ago - it pretty much sums up my opinion of the ranking system.
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I've heard more and more people say the ranking system isn't even worth paying attention to, and I'm starting to agree with them.
I've had strange things happen in the past during online play, but last night was the King Diamond of them all. As my Baraka launched into a combo, some super-glitch slowed everything way down while the camera swung around, and my opponent was literally sent through the roof of the level! (It was exactly like some lost scene from one of the Matrix movies - totally crazy.)
So, I powered down (had no other choice, as everything froze), logged back in, and whammo - had dropped at least 300 places, into the 600's. Is there some sort of systematic re-evaluation of everyone's stats that takes place? Like, a point in the day or week that xbox.com has to factor in all of the new players and shifts in win/loss ratios? That might be the most likely, since auto-drops in my rank have happened before.
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Just as you said - there's no reason to drop in rank after winning. That is, if xbox.com doesn't shuffle and recalculate the stats as I hypothesized. On top of that, you have people unplugging or quitting when they're in danger of losing... just not worth losing your head over.