According to the market researchers at Nielsen, Google's Android OS has made incredible gains over the past year, and now dominates the US smart phone market with 39 percent usage share. (Android accounted for just 29 percent in the same quarter a year ago.) Apple's iPhone is number two with 28 percent, but that OS has only seen a tiny bump despite great sales; it controlled 27 percent of the market a year previous.

Rounding out the top five is RIM Blackberry (20 percent, and the biggest year over year fall), Windows Phone (9 percent, though that includes Windows Mobile users too), and HP/webOS and Nokia, which are tied with 2 percent each.

Nielsen was nice enough to supply a great chart too, which breaks out the top three Android vendors (and the top 2 Windows Phone vendors).

nielsen_june2011smartphone_0
So. What are we to make of this?

Windows Phone is actually done a bit since the first quarter, when it accounted for 10 percent usage share. But at one-third the iPhone, I mean come on. That's really not too shabby.

And Apple seems to be falling by the wayside when compared to Android. But when you add iPad and iPod touch sales to the iPhone, you see a very healthy iOS market overall. I don't see iOS going anything close to downward anytime soon.