DJ Hero Planned For Later This Year
Beatmania US was released three years back with a quality packaged controller for $65--you can pick it up for $15-20 now if you're lucky enough to find a store with one still in stock. It only had a handful of US licenses and it was PS2-exclusive but they did bring it over to the States and a lot of people had a lot of fun with it despite (or sometimes because of) the insane difficulty curve.
Still, the grandparent is woefully uninformed--this isn't a Beatmania ripoff in any way but the DJ motif. Beatmania plays like DDR with the turntable as an extra button while DJ Hero's controller is a Guitar Hero guitar with three buttons and a turntable instead of a strummer. The first GH was itself an acknowledged ripoff of Guitar Freaks though which actually was three buttons and a strummer so it all traces back to Konami in the end if you want to nitpick. :)
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Then again, there wasn't even the slightest hint of effort put toward the Wii. Guitar Hero will continue to dominate on that front if nothing else, especially with confirmed DLC coming with World Tour. That is, of course, after Harmonix claimed it was technically impossible... y'know, just like including the character creator was technologically impossible (something else World Tour will have).
Harmonix has already announced that RB2 for the Wii will have DLC and online play. There's no word yet on whether the character creator will make it to RB2 Wii yet but it definitely won't be as gimped as RB1 in terms of features.