i have herd that the dark brotherhood is coming back in skyrim and i am very happy with this but since there is many new options i would like to to see more guilds that help towards these options for example a blacksmiths guild that would teach you how to forge some amazing armor details that u can only learn there.

Well some other factions are bound to return as Todd said 'some factions will be returning'

I believe Todd mentioned some new guilds, some old ones. I assume the Mages Guild is out, the Fighters guild is in possibly under a new name, no doubt there will be a thieves guild, but it might just be the native syndicate like the Commona Tong was in Morrowind. The others are up in the air for speculation.

would like the imperial legion to come back and like houses so you can take sides in the civil war which would be awesome because you decide who wins and who rules skyrim or even better if you could become the high king or queen of skyrim

Bards. There is a college, why not a guild.

Let's see, as you said, the Dark Brotherhood is confirmed, I'd bet the courts of Whiterun and Solitude will be joinable, and if there's any Imperial presence in Skyrim, then I'd expect the new College of Whispers and the Synod to show up, and hopefully the Bards College will also be an option.

Of course, we'll also see guilds for fighters and thieves, just not necessarily the Fighters Guild and the Thieves Guild.

Morag Tong FTW!

I'd personally like to become the Head Librarian of the Ysmir Collective.

the mages guild most likely gone now i doubt that the is still schools for magic which mean there will still be a guild

The mages guild split up into two different factions: The College of Whispers and the Synod.

thank you for that info i did not kno