I, too, would like an immersion blender--and for the reason Lawrence cited: pureeing soups. Indeed, about the only thing I regularly used a blender for in recent history was pureeing soup. One reason an immersion blender tempts me--I'm thinking the cleanup will be faster and easier than my regular blender.
Unfortunately, though, no immersion blenders have come along. They appear at Goodwill every so often, but cost more than I want to spend. When sales come around, I've never found one that is a good deal--maybe they sell out quickly once a 1/2 price clearance sale cycle begins.
As for getting all metal to avoid staining, that's probably a good idea. I also don't really like the idea of putting plastic into a hot pot of soup. That said, given how cheap I am, I'd tolerate plastic if it meant I could get an immersion blender for next to nothing.