I have used iBooks for over four years (going on five actually...) and even though I have had multiple warranty (and one non-warranty) repairs on both my G3 and G4 iBooks, I think that they were o.k. (particularly the G4, which I bought new for only $650.)
However, I wouldn't buy a MacBook. They look and feel cheap and the new design for the heat dissipator makes them run hotter than previous models. On the other hand, the MacBook Pro doesn't look and feel cheap and it utilizes a different heat dissipator design than the MacBook so it is cooler to the touch. The screen is brighter and 15" is a nice size for most uses. Remember when a 15" CRT monitor was the norm for desktop computers?
Right now might be a good time to pick up a MacBook Pro because the previous models will likely be discounted to move the old stock. Folks eligible for educational discounts should be on the lookout for special offers at college bookstores, because there can be excellent deals on recently discontinued portable Macs; that is how I got the G4 iBook for $650.
At any rate, figure-in an extended AppleCare warranty when calculating the total cost of a new portable Mac. I am normally against extended warranties, but when it comes to Mac hardware these days I think that an extended warranty is essential rather than optional... The L.A. Computer Company consistently has the best prices for AppleCare; they seem to price it at the educational discount level, which is the best deal that I have found online or at brick-and-mortar stores.
Now I am off to the U of O Bookstore Web site to see if there are any MacBook Pro specials posted!