Bent redstone does not power adjacent blocks (eg, hoppers, dispensers, ...)
Video at http://youtu.be/03krIvYEtVU (uploading)
I first noticed it on a 1.7.2 Multiplayer server, shown in the attachments (yes, the client is modded, but it's multiplayer). I then switched to a vanilla 1.7.5 singleplayer world to see if it still existed, see video.