Earlier quoted context omitted.
I am not an immigration lawyer, but this is my understanding: The H-1B is similar to the TN but each have their pros / cons: TN is much cheaper (~$50 + lawyer fees) and there is no cap / application deadline. You apply at the border so there is also virtually no waiting time assuming you get it. The downside of the TN is that it is a "temporary" permit. Technically it's not actually a visa. It simply allows you to wo…
One correction: > "In other words, you are not supposed to apply for a green card while you are on it." You can actually do this, it's very painful but it's not rare. The gotcha is that the moment you leave the country your TN is kaput, so you're effectively trapped in the USA until the green card process is complete.
Not quite true. Once you've filed for adjustment of status (which you can only do once your priority date is current), you can also file an I-131 for advanced parole, and after receiving this, you can leave and re-enter the US with it. Technically you're not on a TN anymore though.