How do you know ? Why not: 75% Windows, 20% Linux, 5% MacOS. And the number of Linux users might be growing rapidly ...
as I said I'm not on the programming end. I assume it is for scalability and use on a number of platforms. metooxx, next time quote my entire sentence and not a piece. I said my comments were based upon others commenting on the boards, do a search. My own experience though is that I can't notice any difference between using java (TWS) and a windows based programs. I see absolutely no delays and using hotkeys can enter orders much faster than the windows interfaces supplied by the exchanges. As I'm sure you know, it's the backend that counts.
I sent an e-mail once, and got no response. I am able to get them on the phone however, and often find them to be abrupt (not all of them however, not fair to bash them all)
Wow, I had almost the same problem with IB/PHLX about a year ago! ...except for the margin issue. I do my best not to route to PHLX anymore.... I feel your pain...lucky enough for me though they busted the trades the same day cus I raised a fus....