Engadget provides some further confirmation, although from a seemingly unconfirmed source, that Core 2 Duo (Merom) MacBook and MacBook Pros are due in November.
We just got word from an IT guy at a Swiss university who claims to have the gotten the scoop on upcoming MacBooks from some sales reps. Apparently they've confirmed Core 2 Duo processors will be making their way into upcoming MB and MBPs this November, and were even kind enough to let our tipster "pre-order" a C2D MacBook.
It should be noted that Apple's sales representatives are traditionally not told about pre-release products. That being said, AppleInsider has stated (and reiterated) that they expect the full laptop line to be refreshed by the beginning of the holiday shopping season in late-November.