3 red X's is all you get. You get blue X's after your classes if a correction is made, otherwise it's blue slashes. You're verified when a date shows up in the upper right of the printed application. Some schools get the verified app pretty fast because they're set up to receive electronic transmission (like Keck, Stanford, Michigan, Pittsburgh). Other schools get mailed only a summary app (which they mail out in batches every Monday -- so probably the Monday after you're verified) and then somewhat later (unclear how much later) they are mailed a complete paper copy of your app. My lawyer got this info from the Director of AMCAS, so I'm pretty confident about it.