Igniting a revolution IS pie in the sky. The movements in Iran will be on the strategic, not tactical level. The exposure to social media isn't going to be the instant-gratification panacea our current culture likes so much. But it has exposed that voting block to outside thoughts and ideas (not necessarily Western thoughts and ideas, and they don't have to be) that scare the current establishment. This isn't going to be a giant "ooh, democracy, let's get right on that". But it has forced the government to acknowledge and address the desire of Iranian youth to do things like 1) engage the rest of the world (via social media), 2) access Western/outside entertainment 3) shift social norms such as apparel, public behavior, and so forth and so on.
To give you an example, Facebook has been banned for quite a while, but during the last presidential election, all candidates (to include the fundamentalists, not just the progressives, and yes "progressive" is a relative term) had both Facebook and Twitter accounts. It's a small change, but a telling one when they're forced to violate their own rules to keep up with the populace.
So no, Iranian change won't be quick, but it is occurring, and in ways the government is having a hard time controlling.
On Israel - I'm really not sure how many people ACTUALLY want to nuke Israel. Nuclear strike capability, sure (that brings the regional/global standing we've been talking about, and domestically makes the government look good/competent), but IMO, while there are some who would eliminate the Israelis, for a LOT of Iranian politicians, it's more about having a common enemy for your Two Minutes Hate in the state-controlled messaging than it is about an actual ideology.