Kissing someone's hand is the ultimate respect anyone can show in Iran. But when you kiss a higher authority it only means you have total obidence toward that person.
That said, "the endorsment ceremony of Mr. Ahmadinejad", the new president of Islamic Republic, can be summarized in one picture: A president who kisses the hands of the Supreme leader. This means Khamanei and his followers, mostly from Revolutionary Guards, have consolidated the entire power structure of Iran.
The whole struggle of the reformists has always beento avoid this kiss. Never a kiss has been more meaningful.