To Amolkool:
I have not processed TN visa before but have limited knowledge on it. You can browse other immigration websites and find more about it.
TN Visa:
- Easy to process - just goto Canada - US border, show offer letter, your qualification / experiences and Canadian passport, get TN visa stamped and enter to US immediately.
- TN visa is not limited by annual quota, as opposed to H1B which is limited to 65000 currently.
- It is only for 1 year but easy to renew. There is no limit like 6 years in H1B.
- If something goes wrong in US job, you can always go back to Canada anytime as you are citizen (and may be comeback if find another opportunity or stay and work in Canada).
- Easy commute to and from Canada whenever required, just like another US state.
- I am not sure how much fees for TN visa, but definitely should be far less than H1B.
- Due to above benefits, TN visa is more preferable by US employer than H1B sometime.