I imagine that Linderman, Mr and Mrs Petrelli, Hiro's Dad, and Simone's Dad were the group that Linderman mentions. Some or all of them go on to found OWI. It appears that Mrs. Petrelli has ties to OWI (knew of Claire's situation and had the Haitian secretly working for her), but she's not aligned with them.
I loved the bit at the end. Future Hiro's timeline isn't linear and he seems a bit surprised to meet himself. The Bennett/Parkman/Ted team-up has a lot of great potential (the "burn bright, not hot" was awesome). I almost feel sorry for Candice (illusion girl), because once Jessica gets a hold of her, it's going to be ugly (protecting Micah is the one thing her and Nikki agree on).
I agree, justvinnie, that Peter probably has to see/experience a power being used in order to duplicate it. He's only ever seen Sylar use TK (he must've turned off the super hearing, since Peter's screaming didn't affect him) and so that's all he can use.