I played a little with another "list" program that has the bar code feature. Its iPhone "scanning" feature only works with a 3GS and above, and I only have a 3G, so I only could use the manual entry feature. Upon entering the code, the product name would automatically appear. One problem with (the free version of) this program is that it won't accept and does not recognize the old 6-numeral codes (e.g. Heinz Ketchup). And, so far, its online database doesn't allow editing of the product once the bar code is entered.
I much prefer Price Book's handling of price comparisons, and look forward to further development of the "list" feature.