Indeed. I agree, past Iranian presidents have been pretty immature, and quite frankly stupid in publicly encouraging nuclear enrichment, in return for crippling sanctions that hurt most of its citizens. They couldn't see the big picture and simply wanted to look hard. This is school boy bully behaviour and didn't help the country long term at all.
The current Iranian president seems a lot more sensible. He wants to talk, he wants to be part of the worldwide conversation, and over and above his predecessors immature behaviour, he is focussing on his people's well being. That's leadership. We need to keep talking with Iran, we need to listen to them and they listen to us. This surely is the best way for long term peace? If someone doesn't take the high ground and give in, we'll just be in a silly stalemate for another 200 years because of some issue that is in the past, between people that aren't included in the conversation any more.
Iran has stood and given ground, we (the west) have also given ground. This is sensible negotiation. If we continue to drag up past arguments and events, blame each other for whatever has happened before and refuse to help them because of statements made by past presidents, then we're no better than boys in a school playground. We need leaders who are prepared to talk, negotiate, and give in sometimes, rather than just puffing out your chest and wielding power. Obama in my view is one of these people (and no, I'm not American and don't live in America).