So they are pretty much just marketing it as dual channel for a little extra cash?
Yeah, but that's only part of it. These sticks have been TESTED in dual channel, so that means your RAM comes from the company tested and guaranteed to run in dual channel. That's the difference between high performance 'DC' ram and ValueRAM. Even though all it requires is two exact sticks, sometimes DC won't work if you got 512mb and then another 4 months later, just because computers are fickle like that. Sometimes it can be a gamble is what I'm saying.
The high performance RAM sticks are not only tested to make sure they run in dual channel right out of that package, those sticks are also designed to run at the best capability a RAM stick can where as ValueRAM is thrown together at the bare minimum specs a RAM stick can be made in. You're paying for part quality, the extra effort towards building those quality sticks, the name, and the fact it's been tested. In the case of OCZ Platinum Series Rev. 2 RAM it has been OC'd up to 285 in some cases, so it's darn worth the extra price IF you know what you're doing
EDIT: Oh yeah and high performance RAM always comes with heatspreaders, and some good heatspreaders are like $10-15 bucks so that's something to consider into the price.