I am not a Thomas fan, and thankfully, neither kid is either, so I'm happy to ignore them.
I always considered it to be a giant toy- and merchandise racket, and that was even before a hundred million lead-tainted trains were set loose into the marketplace to poison Our Children. And before I found out how haphazardly non-canonical the TV shows are. And before I found out that The Rev. Awdry's original stories were even more conservative, authoritarian, and classist than the few tedious episodes I've seen.
The only unabashed good that Thomas served was providing a steady gig to a pioneering comedian, George Carlin. And of course, now he's dead. And the only really interesting thing--and it wasn't even that interesting--was the oddly archaic model-based animation technique used in the show.
And now it turns out that's disappearing into a computer-generated fog. So basically, the revelations in this Metafilter thread about Thomas's impending CGI demise pretty much seal the deal for me. That train has left the station for me, but for good.
Thomas' Pixelated Pickle: Or The Year in Thomas [metafilter]