Android address book vs. Xing address book

Well, unlike the Facebook and the Linkedin address books the Xing address book only mixes into the Android address book after installing and launching the Xing application. Maybe that's because the makers of Android have nice deals with Facebook and Linkedin and not with Xing, but it just works a lot different. You can join your various "standard" entries within your Android address book, and the Xing address book entries are not reachable and joinable like that. Instead the Xing app adds a reference from a matching Android address book entry to a Xing address book entry.

bulk upload of events in XML at XING

At this link XING tells us, that they accept XML files in a certain format for uploading events to their site. They supply us with some nice but rather informal documentation in PDF, but there is no schema. Now that made me a little curious today, I downloaded their template file, created a few variants of the sample entry, and running trang I created a RELAX-NG schema file (anybody interested?). trang seems to not recognise date-time values of tags, so that always needs a little manual post-processing.
O, yes, I proudly uploaded one such event that way. (Actually on the first attempt I got the year wrong, that was quite embarrassing.)

Google Mail Contacts is my personal killer app

Serious!!!
Once again: it syncs with the iPhone address book.
I use it for reverse look up (phone number to address book entry) together with my telephone system in my home office, and that's build around an AVM "FRITZ!Box". The glue software got implemented by myself in ruby (w/o Rails).
Why ruby? I thought, I could make it run with Cocoa Ruby on the iPhone. But you know yourself: Apple fights those kinds of things. And just for running it with a GUI on a usual Mac OS X? No, that's not worth my effort.

Update / 2010-06-16 11:45:
I forgot mentioning xing.com here. Downloading vCards from xing and adding them here – that's just awesome!

I really love using vCards and profiles pictures from Xing

I "always" also "copy" them for my Google Mail address book, which gets synced with my iPhone's address book. This really makes my life so much easier  – recognising resp. remembering people by their faces is so much easier.
Update / 2010-06-16:
I forgot to mention, that I always use Xing's vCards for new contacts to create resp. complete their entries in my Google Mail resp. iPhone address book.