Yes, the CB-Plugin is really good!
I have been using it for some months now, and I think it does a nice job.
Although, as Daniel says, it only works with com_content, meaning that it actually DOES see comments in other sections (like Blog etc), but the link goes to the same ID number in the com_content, rather than for example the Virtuemart or whatever.
Would be almost better for it NOT to see these comments actually... :/
Despite this flaw, I still have it there, as the benefits in my case make it acceptable.
Looking for ward to the next version of this!