The major cause of my skepticism is that electromagnetic radiation in the radio frequencies used by mobile phones (UHF) has wavelengths of around 10 to 100 cm. These energies are only high enough to cause bond rotation and vibration, not homolysis or ionization. If, on the physical level, this is true...what is the mechanism responsible for purported biological tissue damage? Government experts have agreed with this logic for decades.
Before people look at the UHF radiation, they should consider alternative explanations, nearly all of which could be fixed easily: I know that some heat is generated by the phones, and there can be some constructive interference, as well as issues with the batteries and materials in the phones themselves. If it is the case that cell phones cause health issues, I'll bet the ranch that one of these is chiefly responsible.
On a lighter note, check out this hilarious video about Expelled! It's supposed to poke fun at science & scientists, but as with everything else, it just makes creationists look stupid.