When I first read about the dastardly plot to blow airliners out of the sky using some handy bottles of hair gel and sport drink bottles, my little engineering BS-detector went off. This is the little warning that goes off in my head that says "This is too good to be true, so it probably isn't".
However, as with most everything reported on terrorism and security these days, the articles were rather short on facts and long on "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAHHHHH!".
Fortunately, The Register, my favorite bastion of sarcasm, scorn, and skepticism, wrote this article on the subject, which says, basically, that it's not as easy at it sounds.