I would suggest you're both right. The reason I said that a 1GB card was worth it was from reading several various sources and here's just one example:
http://www.bjorn3d.com/read.php?cID=1899
It just seems that if you're going for a top grade card, you're more likely to wish you found an extra $30 but if you're just a casual gamer and do a lot of other things with the card, you won't miss the 'extra bus' or memory. If you don't play those games that take advantage of the extra memory, you won't miss anything.
I like the idea of waiting for a sale or price matching in order to get a lower priced 1GB version but that's just me. I'm more likely to go for an even cheaper card, though...lol... however, these GTX 460 cards sure are temping. If ATI wasn't so crappy at their Linux drivers, I probably would go for a cheaper ATI card, though. If I can find the funds, I'd choose a 1GB GTX 460 card. You won't miss the extra $30 or $40 if you're willing to spend over $200 anyway (is the logic I'd use!

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