There aren't any HSPA+ phones yet, so all we can go by is the released PC card. In some head to head testing, it beat the similar Sprint card. Would it always or in every location? Maybe not, but it shows the tech is obviously competitive.
That's the way Sprint (and Verizon and AT&T soon) are attempting to use it, but that doesn't make it correct.

There is a set of IMT Advanced (International Mobile Telecommunications Advanced) requirements that must be met to be considered 4G.
WiMAX and LTE
could eventually meet the requirements, but they certainly aren't right now. The wiki article has a pretty good description of the situation.
http://en.wikipedia.org/wiki/4G