"Then I hope the price of ProQ 2 is $6.75!
A feller can dream caint he??"
 
$69.95 upgrade; not "cheap", but it is FF!
 
Tom

The upgrade price seems reasonable, but will I still be able to use the old one if I find that the new one is upgraded more than I want? Does this version replace all the old instances of my old version or will I have a v1 and a v2 on my system when I am done?

No they are entirely separate. Q1 will remain untouched even if you only install the Q2 trial. Q2 can read Q1 presets though.
 
EDIT: Also, even if you don't like the new features, Q2 is supposedly twice as CPU friendly.

If they hold to previous convention, the new DLL will be called "Fabfilter Pro-Q 2.dll" and be treated as a separate entity by SONAR, with its own CLSID. You'll therefore be able to use 1 and 2 side-by-side with no problem. 
 
I also suspect that this time they'll do away with separate mono and stereo versions, so there'll likely be just one DLL. Just guessing, but that's the way things have been going. The plugin is smart enough to know when it's being presented with a mono source and goes into mono mode automatically. That's a nice convenience, since weird sh*t happens when you use a mono plugin on a stereo track or vice versa, and sometimes you change your mind about the interleave or the interleave gets changed internally by another plugin.

The vst2.x has a separate Pro-Q 2 (mono).dll but the vst3 does not.

No separate side chain dll's with Q2 vst2; that's what I'm seeing.
I haven't tried it, but I assume that it (vst2) side chains.
T

Been playing with the demo of this thing today, and I gotta say those FF guys are GUI geniuses.  What a pleasure to use ... so intuitive, with quick and smooth control action.  No glitches or other weirdness -- totally stable on my system, even when applying lots of wacky filter shapes (it's mind-boggling how many different curves you have to choose from). 
 
I was curious how the EQ Matching feature would compare against the one in Ozone.  A quick test on a couple of vocal tracks yielded very similar correction curves, but Pro-Q was easier since it didn't require the step of capturing each track separately -- you just send the reference to Pro-Q's sidechain and it takes it from there.  Cool! 
 
Right now, I'd say that this is probably the ultimate general-purpose EQ plugin, when considering ease of use, stability, CPU usage, features, and sound quality.  It may not be THE BEST in each of these categories, but I can't think of anything else that is so good at everything.  Well done, FabFilter!
 
Cheers,
Eddie
 

$87.56 for me. I'm happy. Can't wait to try it out. Happy Eq'ing everyone.

Yup...tis sweet indeed. I love the analyzer capture where one can just freeze then pull down just the offending bump. Plus...a keyboard visual as well. Plus much, much more. Kudos FF!

Wish the FabFilter line was available as prochannel modules with flyout like the prochannel eq module does.