I'll readily concede that the MG name might still have a good chance to succeed again in the US. Basically, though, I'll believe this when I see the cars offloaded from transporters into local dealer lots.
From the enthusiasts' point of view, it might be a hard sell, since this new company has virtually no "track record" in the US or much of anywhere else outside China. From the general public's point of view, it will likely, at the very least, take a marketing/advertising campaign at least as good as that BMW put forth for the new Mini especially in the US. Amongst car folk like us, the Mini was always iconic. To most of the US, though, where only about 10,000 Minis were sold 1960-67 (we got more Triumph Heralds, for goodness sake!), there wasn't much name recognition to build on.
We'll see. I'm a bit bothered by some reports that the company seems to want to make the marque rather more upscale and not the "middle class" or even "every man" sports car it was in its heyday. Come up with a reasonably priced and capable competitor for the Miata and Solstice, and you could have something. Go much further upmarket, and it might be much more difficult.