In my experience only Windows 7 has passable MTP support. On Linux I had mixed results with gvfs and mtpfs (slow and crashy). jmtpfs [1] is a nice replacement, though. Google also released an application for OS X [2] but I can't try it since I don't own an Apple computer.
My solution to the problem was to install a WebDAV server (such as [3]) on my device (Galaxy Nexus) and access it wirelessly.
[1]: http://research.jacquette.com/jmtpfs-exchanging-files-between-android-devices-and-linux/
[2]: http://www.android.com/filetransfer/
[3]: https://play.google.com/store/apps/details?id=com.theolivetree.webdavserverSupport for the USB Mass Storage protocol has been deprecated in Android in favor of MTP (Media Transfer Protocol) starting with Ice Cream Sandwich.
The experience in Windows and on Linux is just as poor with this phone. (I love the phone, though.)
This is 100% to blame on Samsung, sorry.
Even though my Samsung phone is seen as a USB device (and it works on MAC OS X), but maybe in the newer models they removed this functionality (and called it a feature)
People may complain that iPhones need iTunes but then again it's iTunes not the gigantic pile of crap that is Kies
It was pure engineering tradeoff to improve things in the long term. If anything OEMs would have preferred the old 'just works', sub-optimal, gives-an-excuse-to-obsolete-a-phone, lower support issues, solution. The ball is now in operating systems' court to support this standard in a way it wasn't envisioned to work a few years ago.
Even ubuntu has been slow on this front.
OS X has perfectly find support for media devices, and has worked fine with every digital camera, SD Card or other card reader, etc, that I've attached via USB in the past decade!
Which is the right move in the long term, although it's certainly causing some pain in the short term.