The oil market has changed a lot since then (as have Canadian and American politics), and it wasn't so long ago that Alberta was a "have-not" province getting funds from Ontario and Quebec. Then of course you have the oil companies working in Alberta that are not going to want to mess up the status quo and also have to compete with the existing oil lobby in America.

Even then the American government would need to approve it. the Republicans would be terrified of two more large liberal cities getting into the Union so they would rally everything against it. The logistical nightmare of doubling the border size (which we can be pretty sure the Canadian government isn't going to spend a dime on) and converting everyone to Imperial and USD along with dealing with an en-mass (un-vetted)immigration is going to eat up the next 50 years worth of tax revenue from the newest state.

But really I have to question a lot of his knowledge based on that video, Wildrose is a lot of things but to call them secessionist a stretch too far. Even the parts that might talk about it is mostly a tactic to get Ottawa's attention. The demographics he points to are also misleading, with the lower oil value young people are running out the door, as most people would expect them to since Alberta doesn't have a mature enough economy on it's own to support everyone during the bust years.

At the end of the day it's all a moot point really, since the only main argument for Alberta to move would be the money, and it would be a lot cheaper for them just to give BC half of what they would spend on becoming American to build the pipeline to the coast.