It's true! Expect it to appear on the client next week, on the 14th. Of course, this doesn't pertain to you, since you pre-ordered the aforementioned Excellent Game the first day you could. But you know.
Speaking of Gametap, the service has recently undergone some pretty major changes. First off, it's now international. Secondly, the subscription system works a little differently. You can now use Gametap for free with access to a limited number a games (no, the Sam & Max episodes are not among their number), with paying customers now falling under the distinction of "Gold Membership." Gametap also now offers games for digital purchase a la Steam (on which Psychonauts is already available for the same asking price), as you've learned if you clicked my link to above.
Anyway, I'm not sure how interested some of you guys are in Gametap beyond its Sam & Max connection, but it must be said that it's been making some huge improvements, and between stuff like Sam & Max, The Last Express, Beyond Good & Evil and now Psychonauts, it's got a collection of games that might, just might, be worthy of your ten bucks a month.