Microsoft’s gallery had an aesthetic, to be sure, and it wasn’t high art. But these images, cheesy as they are, were also incredibly useful in their time. It wasn’t easy to quickly find images in the dial-up age, and an entire industry of CD-ROMs you could buy for $50+ tried to fill that niche. You could buy those, or you could stick with what you already had: Microsoft’s clip art.
I used clipart a LOT for newsetters and other documents. I don't always want a photo - clipart is often better at getting an idea across quickly, and I didn't need to worry about copyright because I assumed it was OK to use without permission as it was a part of the MS package. The BING option is terrible - very juvenile and hardly extensive with fewer than 50 options. And by-the-way, most of the online sites for "accessing clipart in MS Word 2010" still say to go to insert then click on clipart. Really - we hardly need such basic instructions when they aren't even correct anymore!