What was originally planned as the "Check Mii Out" channel is now available as the "Mii Contest" channel, free for download via the Wii Shop.
If you go to the Posting Plaza you'll find some interesting Miis. You can't really view them all because there's simply too many. It's better if you just chose "Pot of Luck" to randomly select a set to view if you get bored of the charts.
I've come across a lot of Kennies from South Park so far with my region set to UK. Perhaps too many! Setting it to Worldwide came up with some Doraemons, Ryuk from Death Note, plenty of Narutos and some cute little Anime characters. The Princess Zelda and Link ones were done nicely too!
You can click on the Mii you're interested in and then find out who the Artisan was. As with the DS, the Japanese only have Kana in their names, no Kanji. I think if Western players get curious enough they just might end up being able to read the Japanese alphabet...
There's still a few days before the current contest "Mario without his hat" closes. It'll be interesting to see what people come up with. Good luck to the people entering!
Personally, I wouldn't spend much time playing about with the Mii channel (even for my own Mii) but, wouldn't it be great if Nintendo offered prizes to the winner such as Wii Points?
Now I wonder when the "Everybody's Channel" will be up.