It is fun! It is the best FPS I've played online ever. Note, its beta, there are still plenty of bugs. My biggest and fastest computer only gets 10-24fps, but my older mid-level is 125fps solid. The difference seems to be 64-bit XP vs 32-bit. Regardless of browser, video driver, single head, multi-head, picmip, screen resolution, fresh install or otherwise, the 64-bit machine get's terrible fps (usable, but not as nice) and the 32-bit screams... I've done everything I can, swapped video cards between to two... everything. But playing on the 32-bit is a lot of fun! The skill matching is pretty good, the levels are fresh, some are reworked, some of the good ones from RA3 are missing, but its still a blast.
-rich