If all the differences mentioned was against only with chrome then there is no need to talk about chromium.
of course, there's a need to talk about chromium in this thread. It's the topic, the question involved it, and you said so yourself that "we wanted to know what the differences are". If you were referring to the installation sizes, the sizes show a difference in the way the product installs itself, what it uses, etc. and by comparing installation sizes, you can make certain extrapolations guessing that there must be more than meets the eye (because if they weren't any different, why the difference in size?). Though inaccurate and unconclusive, it gives you a starting point telling you that there are differences which are significant enough to create inconsistencies in installation size.
Moreover, since CD is based on chromium open source we wanted to know what are the differences between these two apart from adding the skin and optional DLS service.
Hope someone in Comodo will clear this for us.
Not one from comodo, but anyway, under the assumptions that dragon is built on chromium and not on chrome, the changelog is most probably directed to comparing chromium and dragon (at the very first release that is). Whatever was added, removed and/or changed as stated in the changelog were most probably features or properties included in chromium.
Do be aware that this post is only an attempt to answer your question. Unless someone verifies them, do not take them for facts. I, too, would like to see a comparative chart between the three (Chrome, Chromium & Dragon), but until then, I'm under the pressumption that whatever is in the first changelog were properties of chromium rather than of chrome (i mean, if dragon is built using chromium, then how can you remove something that didn't belong there? so chromium must have had whatever was said to have been removed. And whatever was added can be explained in a nearly likewise manner). Oh and yes, I'd also like it if they added the version info in the website.
EDIT: Fixed minor grammatical errors.