I agree it's unfair to compare the two. Portables are more in line with personal devices, for example in my household, we all have our own DS (4). Home consoles are for the most part, one per household (we have one PS3 and one 360). So in my case you have a scenario where the DS outsold the home consoles 4 to 1.
Again, portables are personal devices and thus will always outsell home consoles. Apples to Oranges.







