Does anyone have an idea what the state of the arcade games industry is like, and whether or not it is still a financially viable market for companies like sega and namco and alike, and who are the current market leaders?

The only place arcades are still big at is Japan.. other than that I don't really know anything.

yeah arcades are dead in the west, i was in trocadero ( segaworld used to be there) few weeks ago and all the arcade games were old games, they had games like daytona usa and sega rally, i didn't see a single game that came out in the last 5 years

I only have two Arcade places where I live... one is in a mall which I think it's owned by Bandai... and the other is chuck E. cheeses

pretty much it..

State of arcade gaming is decline all major arcade game makers divisions saw loss in  2007 if I remember correctly.

As for arcades leaders worlwide Sega Sammy, Namco cybertainment,Taito,and Capcom

I have 3 Arcade places where i live (maybe more but ain't popular), these are in malls or in movie theaters.

Arcades are for the most part dead in the West. True, they exist in some malls, some movie theaters, and Dave and Busters but you're only going to find DDR clones, House of the Dead clones, and racing game clones at most of those. You'll also be lucky if you find something that isn't five years old.