Considering that the iPhone is very popular and seems to have more features, why would people prefer the iPod Touch apart from the contract/no-contract option?
for some the lighter weight and thinner-ness could be an advantage. also it's probably very slightly faster
You'd be surprised at how much background processing goes on for those phone functions.How so? It has the same CPU clocked at the same frequency, but half the memory of iPhone 4 (256mb vs 512mb). I doubt the omission of a cellular radio would affect performance.
Advantage: no butt calls...
Disadvantage: no built-in GPS...
You'd be surprised at how much background processing goes on for those phone functions.