The LHBS I was at last night had both white wheat malt and the "standard" wheat malt, both by Briess. It gave me a good chance to taste both side by side. IMHO, the white wheat malt tasted a little sweeter and a little less "wheaty", which kind of makes sense since it has a little higher gravity potential. Also, even though there is a little higher lovibond to the white wheat, it appears lighter in color than the "standard" wheat malt which is made with red wheat.
Here's an article I found talking about white wheat. It has a nice pic to compare red and white wheat. I would say, the difference I saw last night was not as noticeable, which may be attributable to the malting process or the different varieties pictured.