different horses for different courses as the saying goes, i currently own both and would not part with either, i'll give my reasons why
200 f2.8= sharp, no kidding, this may just be the sharpest of the 9 primes, all canon, that i own, the only 1 i don't have that's rumored better is the legendary 135 f2,
70-200 f4 non IS, probably the best bargain in the L series for price, just may be canon's sharpest zoom, works just fine with 1.4 tele, no image degradation that i can see, making it a great zoo, or close birding lens, it's a good wdw lens, my only whine is that it's white, i wish with all my heart and soul this was black, it would be making the trip to europe in a heartbeat if it was
weight = i just hefted each of them, switched hands, i can't really feel a difference, maybe 70-200 slightly lighter to feel, however the new IS version does pack a noticeable weight gain due to the gyroscope parts
built in hood is nice, this is a feature that should be on all primes and could be engineered for all internal zooms
autofocus = canon fast on both, no difference i see
my thoughts on this = you may be able to get both of these used for around the price of the new IS version, i hear great things about the new version BUT, canon tacked on a pretty healthy price increase, having said that, many pros and just gotta have the latest and best types are flocking it seems to the IS version, thus their appears to be more of the non IS in great shape coming on the market, whearas the 200 seems to be in slightly shorter supply
if your heart really lies with primes, consider getting a used 200, save the leftover money and when funding permits follow up with the 135 f2, used, this really is legendary, and deservedly so for it's sharpness, but do not confuse it with the soft focus version which is a specialty portrait lens. this gives you 2 fast primes of 216mm and 320mm
i think it all goes down to which fits your shooting style and favorite subjects, primes or zooms
btw my concert bag kit is 85 f1.8, 100 f2, 200 f2.8, all primes, all the time, over in my concert thread, with the exception of the campbell brothers all were done with primes, most of the rhythm and roots shots with the 85 1.8
gary