In addition to ‘Omar Suleiman's warnings that the regime can't "tolerate" continued protests, rumors have apparently been spreading that Friday will be the day of a major crackdown. From what I've seen of Twitter posts, the protesters are being invigorated by the threats, not deterred.
There've been a lot of reports that Israel, Jordan, Saudi Arabia and the UAE are all encouraging Mubarak to hang tough. With friends like these . . . Israel's motive is different of course; it doesn't want to lose a dependable firend, while the others don't want a precedent. And of course at the same time, government rumor mongers are spreading the word it's all an Israeli plot.
Wael Ghonim tweeted last night: "I feel that their last line is being written, and soon we're taking the pen to start drawing our own future." It does feel like a tipping point may be coming. It took 29 days in Tunisia, and the security apparatus in Egypt is much bigger. This isn't over, but the growing labor strikes make it move more quickly.