Rikktor

I agree with a lot of your points, most notably the idea that the 25 man bosses aren't as 'epic' as the vast majority of the 40 man bosses (especially Naxxramas) were. The question is whether the cause lies in the fight design, raid size, or loot gained.

You've said that the new encounters took less time to learn, and yet are much more frustrating due to arbitrary enrage timers and other gimmicks. So what's the difference between the fights in Naxxramas and the fights in SSC/TK? Hydross, Morogrim, Leotheras, Karathress, Vashj, and Void Reaver all have a time based enrage timer. If I remember all of the elements of Naxxramas fights correctly, only Sapphiron (though I don't recall anyone actually having to deal with it), Faerlina, Patchwerk, Loatheb, and Thaddius had enrage timers - and going off of personal experiences these were (save Sapphiron) the most frustrating encounters to learn and kill in that zone. The overcoming of these arbitrary timers could be the cause of the frustration that so many players are encountering regarding TBC raiding. I know my favorite fight in SSC is the only one without a timer (though it is also the easiest).

The other possible option that you didn't mention was the loot. Whilst progressing through Naxxramas almost all of the gear gained was a rather large upgrade over all previously available loot and gave you something bright and shiny to hang around Orgrimmar/Ironforge with. Nowadays people have loot from SSC and TK rotting in their banks (which should be partially fixed in 2.1).

Personally, I feel that the root of our gripes are a mix of all of these things. 25 man content does indeed feel like raiding a glorified version of Zul'Gurub; but I'm unsure as to how one would decide the ideal raid size. In an interview with a Blizzard CM (I'm unsure as to which one exactly) he expressed that the reason for the switch to 25 man size was to make scheduling raids easier, and that they had essentially run out of ideas to make 40 man content as good as it had been. I have a somewhat conflicted feeling on the matter - I do think that Naxxramas was 'the ultimate' of 40-man content, and I would've been really disappointed had they come out with a new zone that wasn't as good.

I haven't experienced any types of raiding outside of WoW, but being from a FPS background I had an arbitrary number of people that I liked to play with at one time, so I guess I'd need to go play EQ to answer your question!