Here is some interesting news on MTP from wikipedia, though
Media Transfer Protocol is a set of custom extensions to the Picture Transfer Protocol (PTP) devised by Microsoft, to allow the protocol to be used for devices other than digital cameras, for example digital audio players such as MP3 players, and other portable media devices, for example portable video players.
The USB Implementers Forum device working group is presently working on standardizing MTP as a fully fledged Universal Serial Bus (USB) device class. When that process is complete, MTP will be a USB device class peer to USB mass storage device class, USB Video Class, and so on.
Since that standardisation would take some time, and I suddenly had some free time on hand on fine sunday morning, I decided to try and see what we can still get to work on darwin.
To begin with, I downloaded the libmtp library from sourceforge, which fortunately enough supports mac already and didn't needed any porting, except for an iconv issue. The problem with libiconv is (which is , btw, a library for converting from one charecter set encoding to the other) that there are simply too many versions floating around. So while libmtp compiles and installs fine, any of the example programs won't run, failing with missing symbols.
That was easily fixed though, by adding -liconv to the Makefile in the examples directory in the libmtp sources. (Search for LIBS = -lusb and append -liconv). With this change, running mtp-detect (which installs in /usr/local/bin) gives this output
Autodetected device "Creative Zen Vision:M" (VID=041e,PID=413e) is known.
Connected to MTP device.
USB low-level info:
IN endpoint maxpacket: 512 bytes
OUT endpoint maxpacket: 512 bytes
Device flags: 0x00000000
Manufacturer: Creative Technology Ltd
Model: Creative Zen Vision:M
Device version: 1.30.02_0.00.16
Serial number: 00023C02FB1FE532E960B05763D234C3
Vendor extension ID: 0x00000006
Vendor extension description: microsoft.com: 1.0;microsoft.com/WMPPD: 10.0;mi
1001: get device info
1002: Open session
1003: Close session
Quite a lot of it actually, but here is the more relevant part
3008: MS Wave
ba05: Abstract Audio Video Playlist
ba01: Abstract Multimedia Album
ba03: Abstract Audio Album
300a: MS AVI
3000: Undefined Type
Quite a few formats there.