According to this report, the United States will seek to keep the G8 leaders from adopting financial sanctions against Iran. That's right - we apparently are willing to talk about sanctions, but not to apply them. (Thanks to Jihad Watch.)
Meanwhile, British embassy staffers seized by the Iranian government will apparently be put on trial. The British are seeking to persuade their EU counterparts to pull their ambassadors out of Tehran to protest the arrest of the staffers.
Then there's always the question of how to keep the Iranians from acquiring nuclear weapons. The Iranians have just announced that the Europeans will no longer be allowed to negotiate with them (as punishment for allegedly fomenting last month's unrest). President Obama wants to negotiate with the Iranians, while Vice President Biden is apparently giving Israel 'permission' to bomb the nuclear facilities.
Should make for a great meeting!