It's actually an over simplification and the fact is that benchmarks already show the advantages of a biiger frame buffer (i.e. when you apply AA to games). High end video cards with shallow buses (256 bit) and GDDR5 (dual parallel for a 4x effective data rate) are among the best performing desktop cards on the market.
My advice is stick to sources like Anandtech or Notebookreview (full disclosure and self-promotion: I have about 40 reviews on there) that show empirical test results and skip the fly-by advice like this and previous posts. It is usually well intentioned but often wrong.
My observation is as a long time mac user is that Mac users are incredibly technical software users - squeezing amazing work out of apps like PS and ProTools. But y'all are hopeless when it comes to the guts inside.
That's OK. That is why we buy Macs - output is king.
