Because you never looked at it with the 2MASS layer of WWT before? Seriously though, the 2MASS mosaic on WWT sucks compared to the raw data. It's blotchy and pixelated, it's a lot better to get the raw fits data and process it yourself. That's always true of course, but it's especially true in this case. Here's what my processed version of the 2MASS image of CW Leonis looks like:
[link to i319.photobucket.com]
There are still seams from where separate images from the 2MASS survey were combined, but I don't think it's going too far for me to say that my processing of the raw data is better than microsoft's in every conceivable way. It's far higher resolution; this is like zooming in on CW Leonis nearly all the way in WWT. If you're wondering why Microsoft didn't do it the way I did it, ask them, but I did process it by hand which just isn't practical for the whole sky. Still, I think I could have done a better batch job then they did if I had their computer equipment. They really need to hire a dedicated astrophotographer to handle the sky survey image data.