It's been a while since I've had a gadget review, but I got these Shure E2c headphones about a week ago, and after breaking them in a bit over the week, I think I can give my opinion about them.
I've been looking to get noise canceling headphones ever since using David's JVC HANC100's. The JVC headphones has some electronics inside of them that generate white noise (powered by a single AAA battery) to block out the external noise outside of the headphones, which worked well for low frequency noise such as a noisy computer fan, and I'm guessing they would work just as well to drown out those mundane tones of an airline flight. The other nifty thing about these headphones is the retractable cord, which makes it convenient to use even if you don't have any sort of music source to plug into. However, the downside of these headphones is its bulkiness, so if you wanted to jog or exercise with these headphones, you're probably better off looking elsewhere. Also, for whatever reason, I was leaning more towards some sort of earbud headphone.
So after sifting through reviews at Amazon, I finally settled on getting the Shure E2c, which were rated pretty highly and pretty reasonably priced (note: For whatever reason, the price of these headphones fluxuate quite a lot, and I managed to snag these for $65 the day I bought them, so your purchase price may vary :P). Instead of using white noise to block out external sound, Shure takes another approach by making the headphones seal in your ear like earplugs. The headphones come with 3 set of earplugs (foam, silicon, and rubber) in 3 different sizes, giving you 9 standard combinations to try or you can mix and match the earplugs. I initially tried the medium-sized silicon earplugs, but I found them to be too hard to wear comfortably, so I switched to the medium-sized rubber earplugs, and I've been a happy panda ever since. Without any music playing, you feel like you're wearing standard earplugs, but once the music starts, your ear pretty much sifts out any background noise and concentrates on the music. I could have the dishwasher running and David watching a DVD at a normal volume next door on our 5.1 sound system and not get disturbed as I worked in my room. In fact, I would say it's probably dangerous to run outside by yourself with these on because you probably wouldn't be able to sense any "dangerous" sounds fast enough to react. In terms of sound quality, these phones provide a very clear and consistent sound, and with the noise-cancellation, you probably will hear parts of your music that you never heard before! Those who are into bass might find these headphone underwhelming, but you'd probably be looking for a different type of headphone altogether if you wanted to listen to bass all the time.
Anyways, if you're looking for a good set of earbuds that can isolate your ears from the rest of the world while you listen to your music, definitely give these a look!