its crap stupid format, only 'ok' for audio and stuff that doesnt have much motion in it. but its small, thats the reason.
Best reason i can come up with the quality to size ratio is by far the best, and the format is alot easier for many people to play with a wider range of audience.
Maybe it has something to do with filesize. Rmvbs have a small filesize and decent quality. I personally grab RMVBS myself because of the small filesize. I ca easily DL an episode quick. Plus, with my monitor I can barely tell the different btwn MKV and tv RMVB quality.
I guess alot of people watch them on thei notebook/computer. I, myself, dl the mkv or mp4 to watch on my big screen lcd. rmvb looks terrible on my 65" lcd. I also keep my tvb series. I leave them on my nas server.
It did serve a purpose back then when people had slower internet connections and low screen resolutions. Nowadays, with faster internet and 1080p monitors being the norm, rmvb seems kinda redundant.
oh yeah forgot u were on the tiny island on the other side of the world... =/ anywhere else its still only a few secs to dl in hd LOL