*sigh* I wasn't going to jump in until stickball's last post. There is so much wrong in there....
Starting with the XBLA statement, If you count every title available the Wii has an unmached list of backcatalog titles including most of the best games of all time already on there, and has been making globs of money on them. When they DO finally start adding Wii Ware titles (some of which look just as complex as even the best XBLA titles) there is no reason that the XBLA library would even be close to the Wii's.
Nintendo announced many major 3rd party companies have made begun production on Wii Ware pitches including giants like Capcom (Yes, I know XBLA has SF2HD) and Square Enix. Most XBLA titles are made by Microsoft or Microsoft 2nd parties. With by far the weakest back catalog I'd even go as far as to say that XBLA has the weakest prospects of any system in downloadable games. The PS3 right now probably offers the best due to full games like Warhawk.
Compare downloadable game scores:
http://xbox360.ign.com/index/reviews.html?constraint.bool.game.xbl_arcade=is_true&constraint.not_null.article.overall_rating=is_true&ordering.order=desc&ordering.attribute=article.review_date&constraint.return_all=is_true&constraint.max_rows=40&constraint.locale=us&sort.attribute=article.overall_rating&sort.order=desc
http://wii.ign.com/index/reviews.html?constraint.not_null.article.overall_rating=is_true&ordering.order=desc&ordering.attribute=article.review_date&constraint.bool.game.playable_download=is_true&constraint.return_all=is_true&constraint.max_rows=40&constraint.locale=us&sort.attribute=article.overall_rating&sort.order=desc
Even now, the Wii's massive backcatalog blew away the 360's XBLA selection in under a year. Absolutely destroyed it in fact. With the adition of major 3rd party games on Wii Ware there will be no comparing the two.
Now, on attach ratio, it's ridiculous to call it's first year attach ratio the attach ratio of it's lifetime. It's even more ridiculous to criticize Zack & Wiki sales based on the first week when A) Most retailers didn't stock it in week 1, B) Many games have experienced this problem and still been very successful such as the game my avatar is from, and C) Capcom themselves said they were more than satisfied with week 1 sales.
Also, if attach rate and first year TP support meant anything, the DS wouldn't be the leader right now. Instead, the DS has the overwhelming majority of TP support, even with a mediocre attach rate. The DS also had 2 full years of crappy TP support, even if you wouldn't know it looking at it right now.
