I was just over on Brickset.com and they're reporting that the 8043 is already gone from S@H. Sure enough, the 8043 is no longer listed on S@H with other Technic sets and the Google cache version from earlier today has the "Sorry, item is not available in this country:" message.
Apparently there is some sort of issue with the linear actuators used to raise and lower the boom. Eurobricks members are reporting all sorts of issues from poor performance to burnt out motors. One member emailed Lego and they are obviously aware of the issues and are currently working on design changes for a re-release.
I don't normally buy Technic sets, but I was really looking forward to this set. It's hard not to appreciate the complexity of this beast. If any one else was considering buying the set and can't wait for the re-release, Amazon is already sold out, but you can still grab them from Target.com (~50 left as of posting) and Walmart.com (~25 left as of posting).
http://www.target.com/4567590-LEGO-Technic-Motorized-Excavator/dp/B003F82N0O/
http://www.walmart.com/ip/LEGO-Technic-Motorized-Excavator/14145846
The reserved me is saying wait until they get the problem fixed and buy the re-release. The impulsive me wants one now in the event Lego can't find a cost effective fix and scraps it. What to do? What to do?

