Refreshed internals, lower price point possible.
Apple's New $899 Product is an LED Display and Not a MacBook? [Update]
AppleInsider also confirms that new displays with a DisplayPort connector and MagSafe adapters are likely to arrive. The rumor site also believes the $899 product is likely a 24" Cinema Display.
This throws some doubt into the remainder of the analysis for the part numbers that were leaked.
Update: It should be noted that the $1299 presumed MacBook price point is labeled "Better" so it represents the mid range price for the MacBook. We still don't know what the entry level MacBook price will be.