I've been working with this setup on my HTPC now, and I have to say it's a great solution. The absolute pointing in X is really intuitive, the fact that the WiiMote works over bluetooth makes pointing at a receiver, like you have to do with IR-based remotes, superfluous, and the fact that I can randomly pick the WiiMote I can reach best is icing on the cake.
The combination with Mame is even more fun: a lot of games are made to be enjoyed with 2 players in co-op mode, and are just as enjoyable with a friend, lounging on the couch with a beer.
Disclaimer: It probably isn't legal to download and use Mame roms; you should dump them from the arcade machines you own. I do not know where you can get them otherwise, please don't ask. No arcade game manufacturers were harmed in the making of this article.