As the title says i wonder if this will be a problem. Do we know if you choose a certain ability are you stuck with it, respec?

Also things like choices made in the story line or factions you choose to go wifh. Can you be in the fighters guild and be in another guild. I just hope the first character we make isnt a test dummy. I like spending all my time with one guy and i hardly ever change them. Or msybe i spend two hundred hours on a guy and decide i want to dive more into magic. Are there limitations or is it more free with loadouts. I have a feeling you would want to run a totally different build when running in a group and running solo.

In can in in multiple guilds like the fighter's and the mages' guilds but also in multiple player created guilds. The choices you will make will be subjective to the story you are involved in, mostly. You will have choices like becoming a vampire of course will will affect on how you play. But the majority will affect you in a local, acute ways.

Paul Sage said it will definitely be possible to respec in the interview with gamespot:

https://www.youtube.com/watch?v=-ZpNe5iredw

(at 20:33)

Its an mmo, if you would have to do an actual irreversible and meaningful decision, players would go nuts. So there is only cosmetic stuff, none affecting the gameplay really

What really already bothers me is talk of this time travel quest! You are presented to either aid the Orcs or help the Bretons at the expence of the former...the outcome will pee off either one of these lasting the entire game, thus changing how you are perceived by NPC's!

Not sure i like this!!!!

dont do that quest

Right, unfortunately that is not an option...

it's TES, not doing the main quest always was an option!

however, the difference will be which NPCs are talking to you, while the actual quests remain the same. so what?
it'll be meaningless decisions over and over again, just like in Skyrim, Oblivion, SWTOR or [insert any mass market game featuring decisions/karma]