John Carmack is famous, kinda.
Amongst game programmers, we certainly pay more attention to who writes the code, not just who designs the game or draws the art. Most gamers are more likely to know of Cliff Bleszinski than Tim Sweeney, but programmers are more likely to know of Sweeney.
Besides, true that you don't really know the "big shot programmer" in games anymore, mostly because there is not anymore one programmer, you see a full team creating an engine. so they blend in the product.
About Carmack and Romero, I guess it also helped that Romero made a fool of himself after the "breakup".
Perhaps a little off-topic, but if you're interested in a slice of history, have a look at what Sweeney made before the Unreal engine: http://en.wikipedia.org/wiki/ZZT
I find this podcast really interesting, because you hear stories from people who are otherwise just another name on the credits: http://irrationalgames.com/insider/irrational-podcast/
Bill Gates is also an interesting example - he is known to pretty much everyone for a number of reasons, among those, probably the least, but still, for the versions of BASIC he wrote.