Disclaimer; This is based off what I've heard, not what I've experienced. Everything and anything written here is subject to change as more gameplay elements are revealed.
So, there's a lot of speculation surrounding Bethesda's online RPG. I want it to be good. I whole-heartedly doubt that it will be considered one of the greatest games ever made, either sitting in the "Terrible" or "Painfully average" category of online games. Here's my reasoning;
This is by far my biggest concern. After whats happened with Diablo 3 and Sim City requiring you to constantly be online in order to play (and both of those games failed on launch as a result of a huge surge of people on the opening days), then I've got no reason to entrust Bethesda to do such a thing correctly. I mean Blizzard and EA are huge companies, with a track record of being relatively stable in terms of their games being technically functional. Mostly. Bethesda on the other hand have had a track record of glitches, bugs, errors, and poor optimisation in many of their games. What on earth makes them think that they are capable in succeeding when two of the largest gaming companies in the world have absolutely failed? Especially after shenanigans like this. (To their credit, that was two days after release, but they can't do that if they plan on making an MMO, it has to be fully functional from day 1 or they're buggered).
Plus the idea of a mega server scares me. It can go down for any number of reasons; Power cuts, software issues, hardware issues- all of which may be relatively tricky to fix, especially when you've got this huge fanbase who love this series trying to cram themselves into this game.
This is probably something more personal but after about a year of playing it I did eventually grow to like Skyrim. It was only after 8 months worth of patches and 20 optimisation mods or so that I actually felt like I was in this epic fantasy world and not playing a really buggy game where textures pop in and out, people clip through the floor, and the citizens of Whiterun all attack each other for no reason other than "FOR SOVNGARDE" (Although to the games credit it was pretty damn hilarious).
Regardless, once I had the thing working I loved it. It felt great to wander through this huge, empty, hostile wilderness and I'd like to see more games come close to replicating that feel of emptiness, and a great sense of community upon finding a small village. That feeling simply won't happen in an MMO. You'll have people running around T-bagging, people calling each other "noobs" in the chat (and that will happen, as the game does have a large 12 year old following, who likely don't have the same focus in a role playing game as others). I know they're saying they're working on a system to match similar-minded people together, but I highly doubt it's effectiveness in such a huge game. Perhaps that's not the point of this game, but if I wanted to rot my brain like that, I'd play WoW. If I wanted to be immersed, I'd play an Elder Scrolls game, as it's one of the few things I feel the game does exceptionally well at, unlike the combat. Speaking of which...
Skyrim had OK combat. The Elder Scrolls online will have a similar system to it. Whilst I don't think the traditonal MMO method of combat is much better, I don't really see how the combat of Skyrim will fit into a server filled with thousands of people. In terms of fighting, all that will happen is that player A will wail onto player B, whilst player B holds the block button till he or she runs out of stamina, promptly before dying. Perhaps there won't be any PVP in this game, but if there is, honestly I don't really see how it's going to be in any way enjoyable. It'll literally be down to whoever attacks first, as I've never really had a dynamic sword fight in Skyrim as much as I've murdered my left mouse button whilst mouthing the words "DIE! DIE! DIE!", and either wailed upon an opponent until they or I run out of stamina to block or attack with. Additionally, it's relatively safe to argue that the only reason stealth works in Skyrim is because it's kind of broken, and the AI are somewhat stupid and it can lead to some hilarious consequences. Bows aren't likely to be an option in this game, as the main time most people used bows was during stealth, and the main benefit to bows was the damage amplification from stealth perks. I'd imagine they'd re-design to compensate, but assuming the combat is identical to skyrims at the moment (which is what I can assume from what has thus far been revealed), bows are gonna suck. As for magic, I don't feel it's going to be particularly great either. Magic in Skyrim personally didn't seem to do much post-30, and it was normally more effective, both in terms of magicka costs and damage to either use a melee weapon or bow.
I love some of the ideas for this game and I really truly hope they'll work out, but I can't help but feel that they just won't. One of these is the huge battles the game is boasting, in regards to seizing locations and attacking in huge groups. This is undoubtedly awesome as a concept and I'd love to see it done. But, and it's a big but, can it be done by Bethesda? Short answer from me; No. It could barely handle the faction-based castle-capture quests at times, and had some significant frame drops (Not enough to bother me, but enough to bother many I'm sure), dropping to about 30-45ish at times.
I respect Bethesda, I think as companies go they are one of the most ambitious companies on the market; I really do. I love the effort they put into building these massive worlds, both from the terrain-sculpting aspects, to the interior dungeon designs, down to the sheer amount of lore available within their games, but I feel they can't live up to their ideas from a technical standpoint. They just don't seem to have the staff to manage a game that not only involves the player by looking artistically stunning, but also run moderately well.
I feel this is going to be the same for their upcoming MMO. I just wish them the best of luck.