Of course it's going down. It started at 100% by being the first to market. How could it have gone anywhere but down?

Up? It's been 1,5 years since the other consoles launched. It should had stabilized, but instead it's going down like a plane that has been shot.

Of the 16-bit systems... technically speaking it goes SNES > Genesis > TG16 although the Turbo had a better sound chip then Genesis and if u count the Turbo Super CD games then they are better then Genesis and on par with the SNES visually speaking.

Neo Geo on the other hand is i believe a 24-bit system plus the game cartriges are uncompressed (some games were over 700 Megs) so that puts it in a different league then the 16-bit consoles 

Your maths is poor. It's marketshare simply can't stabilize since it's 1 year older.

No, my friend, my maths are not poor. There's no excuse, 360 is losing marketshare because its sales suck. No way to spin it, not even Microsoft can. If it hurts you, too bad, that's the way things are as of today.

Wii has BLOWN past the 360, so just like Wii did, 360 could do it. But it will need to IMPROVE its sales instead of dropping lower and lower.

Truth = MS will lose marketshare until this gen ends.

Of course they will, since they started with 100% of the market! It means nothing about their actual position in the market. You can only draw this kind of comparison when consoles launch at the same time.

Put it another way - the PS2 lost marketshare every month after the XBox and Gamecube were out. Did that mean anything about the PS2's sales? No.

the ps3's market share has increased, but not by as much as the wii's. About 3-4 months ago it was 21.3% and is now hovering over the 22.2% mark. Not big increases but its there.

To the OP:
You do realise if the 360 market share goes down and the PS3 market share stays the same the PS3 will eventually be ahead of the 360....dont you....