Movements like the ones in Egypt and Tunisia fail more times than not. Typically brute force from the ruler is enough to deter them, but it was never used in Egypt. I give a huge kudos to the Egyptian military for what appears to be truly acting in the interest of the people.
And now there have been similar uprisings in Yemen, Bahrain, Libya, Iran, and others. Like planting many seeds in a field, only some of these can sprout into a full grown revolution.
I'm very interested to see how these revolutions turn out in both the short and long term. I fear these revolutions leaving a power vacuum that is, more often than not, filled by militant groups. I do not envy the weight on the shoulders of the youth of these countries, as they face decisions that can shape their nation, region, and ultimately the world. I wish them the best of luck and hope they make decisions for the right reasons.
My personal opinion is that a revolution in Iran would shake the current geopolitical stage to the core. Iran is a country that is arguably the most widely despised, yet most technologically advanced and quickly if not already capable of producing nuclear weapons. The previous Iranian Revolution was quite a feat and may give hints at how another revolution may take place. Should a rather bloody protest succeed (I am looking at Libya), I believe Iran will be right behind it. Will this all lead to good, bad, or the same old? Either way it is very intriguing and something I will be sure to follow very closely.