Mercifully, no talking heads spewing predictable platitudes, like this utterly boring and vapid example from Symantec. Also, no half-assed wanna-be music video, like this awkward example from Ernst & Young. Twitter's is well paced and tasteful.
One of my previous employers, Guidewire Software, produced some high quality recruiting videos (a project initiated before my arrival, my involvement was limited) that are worth viewing (one, two, three, and four). They were carefully crafted for a narrowly defined target audience: bright, wary, discerning software engineers.
The best recruiting videos I'm aware of are the ones from Facebook. Great production values, well targeted messaging, with plenty of authenticity.