When I saw "Scrabble" hit the App Store my first thought was that the game play was going to be painful on a device with a 4.5 by 2 inch display and no keyboard. But somehow, the team at EA, the largest game publisher in the world, has created an app that is not only incredibly fun to play, but makes you forget the limitations of the iPhone.
Scrabble works in both single player and multiplayer (over wifi, or just switching turns) modes. The game designers have tweaked the UI to allow you to easily re-arrange or shuffle tiles, and there is support for many different rule variants. In general, the design is so intuitive that you "get it" within minutes -- exactly the objective for an iPhone game port.
There are still things that could be added to make Scrabble even better - in particular, the ability to play users over the internet as opposed to on the same WiFi. The biggest drawback, mentioned by users in the App Store, seems to be stability issues. At least one reviewer out of two complains that "the app crashes every time" -- although if Scrabble does work, the reviews are generally very positive. I had no problems myself.
With all due respect for some of the smaller independent developers, its going to be difficult to compete with the likes of EA in the paid app game department. The best approach for the "indies" is going to be to release free apps and hope to monetize with advertising.