I haven't seen anyone talk or post about it yet, but according to The Firearm Blog, the GSG-5 seems to be finished. H&K was suing ATI (the manufacturer of the GSG-5) for obvious reasons - ATI was manufacturing and selling an MP5-looking .22 rifle and was advertising it as an "MP5 clone in .22." Apparently H&K and ATI have settled and GSG-5 sales will be ending shortly so if we ever do get the GSG-5 to our shores, which is unlikely at this point, they'd be massively overpriced since no new stock is ever going to be made.
H&K suing ATI over GSG-5:
http://www.thefirearmblog.com/blog/2009/10/16/hk-suing-ati-over-their-mp5-patterned-22-rifle/
H&K and ATI settle lawsuit:
http://www.thefirearmblog.com/blog/2009/10/17/hk-and-ati-settle-lawsuit-gsg-5-sales-will-cease-shortly/
Speculation re GSG-5s downfall:
http://www.thefirearmblog.com/blog/2009/10/21/was-this-ad-the-undoing-of-the-gsg-5/
H&K suing ATI over GSG-5:
http://www.thefirearmblog.com/blog/2009/10/16/hk-suing-ati-over-their-mp5-patterned-22-rifle/
H&K and ATI settle lawsuit:
http://www.thefirearmblog.com/blog/2009/10/17/hk-and-ati-settle-lawsuit-gsg-5-sales-will-cease-shortly/
Speculation re GSG-5s downfall:
http://www.thefirearmblog.com/blog/2009/10/21/was-this-ad-the-undoing-of-the-gsg-5/