Here's a Ryanair rumour I heard recently...
They took on a bunch of people from Transaer (so they'd be A300/320 rated with a fair bit of time logged). They're willing to take on a lot more (Virgin Express etc). and then they're still looking to hire more people.
Like I said - a rumour, and not from the horses mouth. As for requirements I think alvinsmates has it pretty much spot on...