I support World of Warcraft's paid services. I think they're good for the game. I think a lot of the options that the services provide extend our interest in the game, allowing us to play when we might have otherwise lost interest. What I do worry about is how expensive everything is when you start to add them all up. I suspect I'm like the average player who has more than a few max level characters at this point, which means wanting to avail of paid services on all of them could get a little pricey.
Let's take character transfers, for instance. If I wanted to transfer all my characters to a server where my friends play (why would I want to move just one?) it would cost me a hefty sum. Add to that the fact that my wife plays wherever I play so we multiply that hefty sum by two. Imagine if I wanted to change my characters' races to those combinations that were previously unavailable come Cataclysm... how much would that add up to? It doesn't take an accountant to see that it could cost a small fortune.