The back of my Dev edition says "Designed & assembled in the USA" in extremely faint, almost invisible lettering. However I couldn't care less. All the silicon is made in Asia anyway. At least it's less pretentious than Apple's "Designed by Apple in California" on the backs of all their devices.
Sent from my Moto X Developer Edition (XT1053)
Moto X (GSM Developer Edition): 4.4.2
Asus TF101: KatKiss 4.3.1 (#28)
Nokia 3360, SE w580, SE w760 (bad), SE Hazel J20i (stolen)
iPad 1 (sold), Galaxy Nexus (GSM): 4.3 stock (given away)
Wind Mobile $30/mth 5GB HSPA data + unlimited talk/text province-wide