The Macbook has never been a wussy part of the lineup. Until the unibody MB/MBP was announced, the sanest Apple purchasing advice was always, "buy the cheapest Intel Apple laptop, whatever that might be". Even now, the difference between the MBP and the MB is largely build quality, and the build quality of the plastic Macbook is still so much better than that of the Powerbook that the MBP wins mostly on pure excellence and not utility.
I've found that my upgrades these days our dictated by the ram caps. For this reason, I go with the mbp, which has an 8GB cap whereas the mb has a 4GB cap.
I used to recommend the white MacBook, but since it became clear that the top case nearly always cracked I stopped recommending them. Now I would say the 13 inch MBP is the most sensible recommendation.
I have already had the cracking thing repaired under warranty once. It has since done it again. Now that my version of the MacBook is no more, I'm going to haul it in on Nov. 28, 2010 (the last day of my AppleCare warranty) and kindly request they fix it again :-) Who knows, maybe I'll get comped an upgrade.
They'll replace it for you without complaint, but as an Apple Service Provider tech I can tell you, don't get your hopes up about the upgrade. Apple supplies its providers with parts for machines well after their warranties are all up; for a part like that, that's had problems all across the board, doubly so.
I said looks like less of a wussy lineup. The Macbook has always had a much cheaper feel to it compared to the Pro. It doesn't look incredible now—I don't like how non-contrasted it is—but it looks better.
The screen quality on the Macbook has always been terrible. Maybe the new model is better, but the previous versions have had awful off-angle viewing. The screen alone justified the move up to a MBP for me.
