He's not alone, but I think that he is actualy the only one who can post updates that are showed on Twinhead. Haven't you noticed, that he's the only one who is fixing in bug report but here on forums there are other devs active?
Enlighten me, please, who might these be?
For everyone else, the first place to see it is on the Twinstar's main page, where you click the VANILLA button to see VANILLA news and VANILLA related info.
http://www.twinstar.cz/category/vanilla-en/?lang=en
There, you can see the Kronos team roster:
It's outdated and some people are not working on Kronos anymore.
The second place, where you can see Developers, is the bug report. You can actually sort bugs by their assignment to developers who should fix them. There are only 4 names assigned to fixing bugs in the Vanilla bug report.
Eclipse with one assignment. (because he's not a Vanilla dev, he's the Twinhead dev)
jursky with 35 assignments.
Craig with 468 assignments.
Chero with 1669 assignments.
The numbers include both old and new reports, but it should give you a reasonable overview of who does the developer magic.