When the current MBP's were first released, there was a $200 to $400 premium over similarly configured PC's. Now that premium is around $800 to $1,200. So I think a lot of the current complaining is as much about price as it is about hardware.
If Apple is going to take this long between releases they should consider some type of price reductions on their current line as they get closer to the next release date.
+1 I've been saying this for years. If Apple lowered prices over time then it wouldn't be a big deal if they didn't stay up to date with the latest and greatest. Since they want to be the premium maker and charge premium prices they need to stay on the cutting edge in order to stay price comparable to other manufactures.