When you say aggressive link building, How many per whenever are we talking about? 5000 in a week? 5000 per day? News stories at the top of google have thousands in a matter of hours, so I cant help but think you are talking about several thousand plus in a short amount of time.
I feel your pain, me and google are currently fighting a war I'm losing. Got to number 2 for the term I was wanting and boom, down to 550 odd. Given up with that one for now until Google decides it doesn't hate me anymore.
I don't think anyone really knows how long it will take...but for me it has been over 3 months...I am about to go into a depression. My site was getting 5,000 unique views a day. What I do believe is, Google is more sympathetic to non affiliate sites, unfortunately for me...mine is an affiliate site
It is clear from this discussion that people are left in the dark when it comes to penalties, whether they have been imposed and the level of severity, let alone the specific reason for their application. Concerned website owners see their traffic dry up and are left to interpretation and guesswork. If you are one of them, please join our campaign to abolish secret search penalties by getting major search engines such as Google to offer a means to confirm whether a penalty is in place. Our public launch is over the next few days once we have more case studies - please contact me to submit yours. Thank you! Marc