I figure that if we could talk to the Soviet Union and China during the height of the Cold War, we could certainly sit down at the table with a regional power like Iran. Not to mention, most Middle Eastern experts have known for a long time that there is, indeed, a massive divide between the rhetoric of Iran's government and the attitudes of most Iranians.
The New York Times has the highlights of President Obama's speech, during which President Obama reached out to Iran in an invitation to allow it into the International community.
Initial responses seem to indicate that the response among the Iranian people was quite positive, and even though state television didn't pick up Obama's message, many satellite stations did.
Some Iranians, according to NYT, were claiming that the US needed to make amends for previous wrongs, and you know what, I have to give it to them, we might have to admit some wrong-doing. American-Persian relations have been rocky for the past thirty years and then some. Whereas we, as Americans, remember Iran for their seizure of an embassy after the 1979 Revolution, the shooting of a missile into the USS Stark, and support for organizations such as Hezbollah and various Iraqi insurgent groups, Iranians remember the US for some incidents like the downing of a jet-liner in the 80s, support for Iraq during the Iran-Iraq war, and (most notably) for the overthrow of the democratically-elected Iranian government in the 1950s and the reinstitution of the Shah. The latter of these, undoubtedly, gives rise to great cynicism when Iranians see the US attempting to build democracies in bordering Iraq and Afghanistan. The Iranians probably aren't too keen on having nearly 200,000 US and NATO troops in those countries, either. No wonder they act out so much.
Iran has its issues, to be certain. Support for Hezbollah and remarks about wiping Israel off the face of the earth aren't to be ignored. However, we can't take a hard-line stance against every country in the world--we need bend a little on our rhetoric.
What do we have to lose? American-Iranian relations couldn't get that much worse, could they?