When you place redstone in a straight line it look normal but when you start laying them around corners or make them into a cross it makes a wierd
graphical glitch but the redstone functions just fine.
P.S.
In the photo's the lines on the sings represent the patern
Environment
OS: Windows 7
Java version: 1.7.0_51 64bit
Res: 1920x1018
Graphicscard: GeForce GT 640
Fixed for a future version. MC-66970