Cannot wait till Sunday. Here is how I see it.
1. I think that Jon will find out from Bran who his mother is and seek a connection with Danerys. But i also believe that he will also have a dream in which NED fulfills his promise to tell him about his mother as he promised in the first season.
2. Jamie will emerge as a hero and end up killing Cercei at the end of the series.
3. Arya will kill Littlefinger and will be helped in her pursuit by Joguen.(sp?)
4. Sam will prove to be a major factor in the last two seasons with his research and knowledge. He may end up helping Mormont cure his scale, find the glass that will kill the white walkers, and also possibly confirm Jon Snow's parentage. Mormount will join Khalesi and merge with Jon and his Mormount niece to take the fight to Cersei
5. Cersie will need a navy and recruit the Iron born thug(Euron?) in return for marrying him. He was aced out by his niece with Khalesi and will try out Cersei. This will further piss off Jamie. THere will be a sea battle with his niece and her brother.
6. I think that the Hound will continue with the brothers including the guy with the fire sword in helping Jon and Khalesi.
7. But it will be the IMP who will figure out how to defeat Cersie and the Lannisters. THe guy knows a LOT OF SHIT and will use that knowledge to find a way into Cersei's castle from within to open it up to Khalesi's throng of Unsullied and Dothraki.
8. So in the end of this story, it will be the least impressive characters, physically, who will end up the real heroes of this epic tale and I think that is really the lesson that Martin puts out there.
The heroes are:
1. The Imp
2. Arya
3. Sam
4. Lady Mormont
5. Varys (who really is an underrated character in all of this but always winds up well)