The front glass is held on by an adhesive, much like the iPhone 3G front panel (if you are familiar). Using a heat gun or blow-dryer will soften the adhesive so it can be reworked. I would recommend softening the adhesive in this manner and then use some c-clamps around the affected area to hold it together while the glue resets. This is certainly no guarantee, but worth a shot if you want to avoid replacing the whole assembly. I would probably put cloth or padding of some sort between the c-clamps and the computer casing to avoid marring the case. Also, be careful to NOT over-tighten the clamps for fear of breaking the glass. Good luck!