I enjoy the show, and I find the tie-in interesting, in theory, but I have reservations about the game that I can't really articulate. Basically, it's a huge risk for all concerned, particularly the players. What happens to the game if the show is cancelled? (So far, it has already been picked up for a second season.) Some of the tie-in elements seem a little forced. The place where the show really challenges my suspension of disbelief is as a car guy: "Chrysler products are the only cars to survive the alien apocalypse?"
Yeah, it's not a perfect tie-in, to be sure...but it works well enough to keep me engaged and entertained. I started watching the show when it started (episodes are free online about a day after they air, for us no-TV folks), and I think it and the game reinforce each other reasonably well.
I have to reiterate my earlier comments that the game's rudimentary (although slightly improved a couple patches ago) social tools prevent it from being a good "main" game for roleplayers or those used to a more social MMO-type experience. I have literally NEVER teamed outside the auto-teaming that happens in co-op instances (which are fun). A pity, as the game has tremendous potential as an MMOTPS, with its vivid world and superlative gameplay...but such is the disadvantage of games that have to accommodate consoles as well as PCs.
I play a bit most every day, sometimes longish sessions, sometimes not (look for "Red Molly" at an Arkfall near you!). I love the "good combat and no endless running around from point-to-point" alternative when I get frustrated with SWTOR, which my crew from Pinnacle server dragged me into while they wait for more TSW content to drop.* It's a good game...and I enjoy the show quite a bit.
*I'd be happy just doing "mundane" stuff and repeating some of the content in TSW, just like I did in CoH, but I either have to do so alone, or actually force myself to meet new people, something I'm not always good about doing! =P