There have been a couple of people on here married to Americans who managed to renew or get a TN-1, it appears to depend on how dozy the CBP person is who processes the application (or travel without your spouse and it never occurs to them to ask the question).
Obviously if you show up with an American spouse at the POE and they pull out a US passport, you're potentially going to have some tough explaining to do as to how you have "non-immigrant intent". But it does seem to be luck of the draw. Certainly with some of the land border POEs back east they would definitely make an issue of it going by the various comments on here. Even getting in as a B-2 visitor with a US spouse is tricky.
From the sounds of it you do have non-immigrant intent even though you are married to an American so legally there is no reason not to grant you TN-1. So be convincing if the subject comes up would be the best advice.
Bear in mind that it only takes three years to get US citizenship after getting LPR status in the US after you get married (and LPR status takes about a year) so you may want to just do an AOS anyway and become a permanent resident, get US citizenship and then move back to Canada and sponsor your husband. That way if you decide to move back to the US at some future point it's no big deal. The only real downside to doing that is the US foreign tax credit cap, i.e. if you earn over US$87,600 you have to pay US
taxes on it, even if you live and work in Canada.
Your
taxes are going to be interesting, presumably you file as a non-resident and he has to file as a resident. Legally you can do this if you are on TN-1 but it means you can't file jointly. Although a spouse is usually considered a residential tie for tax purposes so I think you can only do that for the first year if you meet the "substantial presence test". Hmm, maybe you could file as non-resident if you filed a tax treaty claim on 8833 as TN-1 comes from NAFTA so technically it is the "Supreme Law of the Land". Bit of a grey area.
Steve.