I do think that TCGs are where the money is( have you seen how many commericals they have to things like Sci -fi shows and/or lucas board games?) I do think they get SOME profit from RPGs.
Apart from Magic and Pokemon, both of which are past their heyday (from what I gather), I don't see any other gooses which lay golden eggs in the TCG world.
Novels might sell, but you'll notice something, novels don't generate the kind of income that some of the card games do, mainly BECAUSE they can always fix things. Novels have to have continuity. Same is true with settings.
It's not really fair to compare, I think...the markets are so different...
Time for some armchair speculation!
Kids and adults get
addicted to TCGs if they're doing their job right...RPGs are more like a hobby rather than an addiction...and I'd assume that fantasy novels from WotC worlds cater to an existing base of fantasy readers, with gamers (from computer FRP and RPG crossovers) acting as a feeding and marketing mechanism on the side.
If you get a hit TCG, you can extract a lot of money over a short time from "users" as the craze spreads. It's a bit like gambling - you never know whether you might win next game - and collecting - if only you had that card!
T-ching!
RPGs have not much money in them unless they're D&D, it seems. It's already niche, and on top of that, difficult to make a particular product appeal to everyone in that niche, as TSR seemed to find out from all reports...
Novels don't necessarily cater just to the "geek" crowd, so make a hit there and the sky's the limit (e.g. Dragonlance Chronicles). Like movies, a good deal of books sell by word of mouth. I don't know how well fantasy books are selling at the moment, but given that they're often evergreens (I saw boxed set of DL Chronicles still on the shelves the other day, Belgariad too etc.) I suspect that it's a lot...
There's also another avenue. Fantasy is apparently hot in hollywood at the moment, so make a hit gaming/novel world with an existing fan base, and you can sell it to the studios like Marvel and DC have been able to do with superheroes. And then it feeds back into selling novels and games.
No wonder WotC wants another FR or DL!