Of course, if you still like transparent wm's, go
for it; try placing them over an area with more 
detail, though. After all, the average user will 
never be able to remove them without hacking the
image ^_^. In my case, since all my wm's are on 
the bottom, they can be easily cropped - however,
I can also easily prove thusly that the cropped
image came from a bigger, more complete image...
:P