I am strongly opposed to the whole 2 weeks notice thing. I feel absolutely no obligation whatsoever to give 2 weeks notice in most circumstances.
One place I worked would walk you out the door the second you gave your two weeks notice. Most places I've worked, when they don't want you to work there anymore and decide to fire you, they might come to that conclusion days or even weeks before they actually do it. You show up to work on a Friday and instead of going to work they pull you aside, tell you you don't work there anymore. Escort you to gather your things and walk you out the door. Yet I'm supposed to give them 2 weeks notice? Yeah, no thanks. If it's convenient for me I'll do it. If not, I won't. If I feel like it will help my coworkers at all I would strongly lean towards giving notice, but I've never been in a situation in my adult life where I can be adequately replaced in 2 weeks.
At my current job, if I found a new place to work I'd take two-weeks off to coincide with when I start at the new place. I'd give the new place two weeks trial. If I liked it I'd wait to get paid for my vacation and let the old place know I wasn't coming back. If I didn't like the new place I'd just return to work at the end of my vacation and let the new place know I didn't like it there.
The relationship between employee and employer is completely lopsided when it comes to hiring and firing. I think there are a lot of advantages to being an employee, you don't have to give any of those advantages up voluntarily. You can bet your *** your employer doesn't give up their power in order to be nice or considerate.