Hey Marcus
Thanks for your input. Yeah, we have a lot of links but then we've been around for 7 years and weirdo scrapers and random replicants of DMOZ alone contribute a zillion links without us even having done anything. Not saying we didn't do link building back in the day (we did, just like everyone else, in what was at the time a white hat fashion but apparently no longer is) but we have had no permanent marketing team at all for the last two years as we've focused on some B2B parts of our business. So frustrating that bad links just kept growing and we're supposed to be responsible for them!
Anyway, as you say, will need to go in a bit harder I guess. eg just because a site is PR0, I didn't remove it before, as some random person with a no marks blog who used our birthday balloon picture on their blog didn't deserve to be disavowed as far as I thought. But, well, I can't take any chances now so will just have to bin anything under PR1 and take another look at links from themed websites (eg should I disavow other blogs that have added us to their blogroll unsolicited even if they're in our vertical? It's hard to tell. What about genuine flower directories? Who knows?).
What's really frustrating is that the whole message from Matt Cutts is "you really shouldn't use this tool" (ref disavow) as you could damage your site but 1. barely anyone takes links down when requested as far as I can tell and 2. given the amount of junk that's been pointed at our site that we're not responsible for (though we are are responsible for some), then I think the contention that very few people would need to use it is a bit optimistic and there's therefore a danger or people like me totally shooting themselves in the foot, given there are no clear rules on the grey areas I mention above.
PS understood that it's not some magic solution and we'll rank #1 for everything afterwards. I just want to get it cleared up and be able to get back to my day job. God knows how a smaller business than us would cope with something like this. Seems to me it pushes the advantage even further in the direction of bigger companies with the resources to manage a screw up like this.
Anyway, blah blah. Time to get the machete out.