Jo90,
Mate, I've been thinking the same thing myself for quite a while now. It would seem to me that when it comes to the pressurised area of the fuselage, there will be no more quick patch repairs to get you on your way. Carbon, graphite and'or kevlar would generally require lots of heat, vaccuum and time to effect a structural repair. Having said that, one would hope that Boeing have put as much research into the maint/repair of these plastic fantastics as they put into the thought/design/promises of light weight/cost saving.
Not much point having a lightweight/economical aircraft saving you lots of money for a couple of years if the first time the fuselage gets damaged by a catering truck/pushback tug/fuel truck/hangar door etc,etc it stays on the ground for weeks or months waiting for a repair scheme!
Believe me, they all get hit sooner or later- as sure as the sun coming up!
With a "traditional" aluminium skin/structure, the worst hits/holes/dents can be fixed with new metal, rivets and some skilled (or even unskilled) labour in a relatively short time. A big hole in a composite structural area would not be quite so easy in my opinion. Like i said, i'll reserve judgement until manufacturer's start coming up with repair schemes but i wouldn't want to be the first to drive a truck into one!