Well those PX100 headphones came a couple of weeks ago, have to say acoustic sounds was quick on the shipping..

To say they are an upgrade over my old JVC folding phones would be just a bit of an understatement. They're just clearly better in every not so subtle way. Much more extension at both extremes, and much improved clarity - a surprising amount of resolution IMHO for $69..
They're not circum-aural, and have open backs, but surprisingly ambient noise does not seem to be much of an issue. And they're reasonably comfortable.

On a slightly different note I have a fairly large number of songs on my iPod that I downloaded from iTunes. Recently I swapped a not so well liked Pixies album for BT Emotional Technology on Swaptree. I have listened to it a few times and realized that the songs I actually like best are none of the ones I purchased on iTunes! I ripped it to the iPod last night using Apple Lossless and removed the original AAC encoded copies....