We had no opportunity to independently benchmark Medfield; the results presented here are the performance figures we observed when tests were run on each of the phones in question. All of the phones ran Gingerbread 2.3.
The Z2460's performance in Rightware's BrowserMark is excellent, easily outstripping the other two ARM-based smartphones. Intel acknowledges that performance would improve in Ice Cream Sandwich but maintains that all the devices would improve proportionally.
In stock configurations, the Sensation and Bionic offer only middle-of-the-road performance in this test, so a great deal comes down to how Atom performs in Ice Cream Sandwich. It should still be in the running but may lead by the same degree as we saw in December.
Medfield, running Ice Cream Sandwich
Since these GLBenchmark results were run on devices with different screen resolutions, they should be taken with a grain of salt--but then, GPU performance isn't Medfield's major push in any case. The point here is that the Z2460's performance is in the same league as its competition.
Video output was a different story. One comparison Intel put together was a 1080p 50 fps video playing at a 20mbps bitrate--or rather, trying to play. The Z2460 was the only device that could actually manage a bitrate that high; both the HTC Sensation and Droid Bionic died when asked to show the clip.
The HDMI playback off the Z2460 was excellent. This is almost certainly a fringe case--phones typically don't offer enough storage space to make carting around a bunch of 1080p video worthwhile--but today's fringe use is tomorrow's mainstream. The idea of stutter-free, high-profile 720p playback would've been ridiculous 18 months ago. Given the disparity between the pace of smartphone introduction and the length of your typical carrier contract, a little future-proofing isn't a bad thing.