Exiftool (Geotagger also of course) writes metadata to the RW2, but it is useless since IMatch cannot/will not read them.
It won't read the IPTC, but iMatch will read the XMP that Geosetter/ExifTool also embeds, and that might be sufficient. I haven't had time to really test this yet - I have not one but two new cameras to play with.
I did some tests with the RW2: I erased the xmp then opened in Geosetter, wrote location + GPS, unchecked "write xmp" in the Geosetter preferences, and saved.
No xmp was created everything went into the RW2. It is displayed correctly in the IPTC tab of Irfanview and XnView.
And more interestingly it is read fine by ASP, IPTC is diplayed in the metadata tab. I converted to a jpg in ASP and the jpg shows also the IPTC. I then asked ASp to write an "real" xmp, it did, contains IPTC and looks normal. Could probably be read by IMatch.
SO if you are brave enough (I am not) you can do everything without xmp.
Do you like your NEX7 ?