| Remember that while guilds might have had experience on PTR, they also had the stats shirts to emulate a fake ulduar gear level.
I do expect a few guilds to clear most of it on hard mode though, killing Algalon might be another story though, since it's a hard mode unlocked boss, there's some good chances he's tuned like total madness unless you're fully geared in ulduar stuff, which means he'd probably be impossible to beat, at least in a week of tries. I fully expect this raid content to last less than a month for Ensidia/other top guilds, for good raiding guilds probably more than that and for shitheads they probably will never do most of the hard modes anyway.
Edit: Oh yeah 10man version might die sooner, but I think most people don't care about 10man progress unless it's actually harder than the 25man(see Sarth). | 