@dj - interesting... we're only sort of 'back' but, yes, definitely an improvement. I'm seeing our Reports section page come up top for a google.co.uk search on 'seo best practice' (i.e. not the actual report page itself which is odd) but we're not there at all for google.com search on the same phrase (see 'seo best practice'). 

Looks like some data centre updates are happening and that our massive 'downgrade' might be being lifted somewhat... watch this space.

FYI - yesterday we effectively turned off our geotargeting and also removed the 'no follow' attribute on all internal links. I'd be surprised if the latter had such a quick effect. However, the former, though only applied to 4 pages out of the 60,000+ we have in Google, *might* have made a difference only because that SEO report did rank so highly, is a Sitelink for us, a PageRank 6 etc. so gets recrawled very frequently. Just possibly such an 'important' page being seen as dodgy could have ruined our entire domain reputation...? Who knows. 

any update on the traffic, Ashley?

dan

UPDATE....

The short story is that our rankings have pretty much recovered which is great. However, we don't really know why they went down (or back up) in such a dramatic way which is frustrating and means it could happen again.

I'm afraid no-one wins the prize as no-one has come up with any better theory than we had from the start. Summary below:

1. The possible reasons for our nosedive:

- Google "glitch" (just possible...)

- A dampening 'penalty' applied to our domain following our large, retrospective, update of our forum links to have 'no follow' (unlikely... we have since updated this so that only external links out of our site have 'no follow' whereas internal links don't have the 'no follow'. But it's possible this big update temporarily freaked Google out.)

- A dampening penalty due to us using geotargeting (different versions of the same page depending on where the user is) on the same URL. (just possible but again seems unlikely given this was only on 3 pages out of over 60,000 in Google's index.)

- A hangover from our recent site migration where 'adjustments' are still filtering through Google's data centres.

2. Some charts and graphs:

- Econsultancy Google SEO referrals - you can see the drop off following the site migration, the subsequent recovery, and drop off again, and recovery again!

- Econsultancy visits / traffic over the same period - what is clear is that our traffic does not vary exactly in line with our SEO referrals which is encouraging as we're not wholly reliant on Google natural traffic. 

- Econsultancy conversion rate over Google nosedive period - again, interesting to see that despite big SEO drop off our conversion rate doesn't actually change that much. 

- Econsultancy transactions over the Google nosedive period - not only is the conversion rate not unduly affected by the SEO drop off but the sales/transactions don't drop off noticeably either. 

3. What we've learned:

- Doing geotargeted versions of web pages *on the same URL* is probably not a wise thing. There is much more detail on this in my Q&A in the Google Webmaster Forums. The Google Employee doesn't say explicitly that the Googlebot doesn't like this but says 'personally' he wouldn't advise it. That said, we're still using this technique to show *pricing* in different currencies to users depending where they are. And apparently this isn't damaging our SEO.

- Doing a big update to your site's internal links all at once probably isn't a good idea. We doubt this caused our problem but, for a large site, with lots of links, it seems obvious that such a large change *could* freak out the search engines. Certainly, there seems little point in applying 'no follow' to *internal* links within your site (as we did, but have sinced changed back) as this upsets/dilutes internal pagerank. 

- Do submit reconsideration requests via Webmaster Tools. We've no idea if they were read or actioned but it my instinct tells me that are *recovery* in each case could well have been to human intervention.

- Do use Google's Help Forums, and other forums, like this one, to post your problems and issues. You get useful and helpful feedback and, who knows, maybe even the attention of Google to help 'fix' things for you.

- The good thing about suffering at the hands of Google is that it forces you to figure out how you might survive without Google. And we've got a lot better at other things (e.g. Twitter marketing) as a result. Also, if you look at the charts above, it shows that whilst Google can drive a lot of traffic, it isn't necessarily driving as much *value* (conversions, sales etc.) as you might think. Which is somewhat of a relief.

- Whilst trying to fix our Google problem we also uncovered a few other problems (like the way our geotargeted pricing wasn't quite working as it should) which we probably wouldn't have noticed otherwise. So this intense scrutiny helped a lot.

@Anthony - I could tell Matt a thing or two about how Google works (or not)... ;)

Actually, we always knew we'd take a hit on the site migration, the interesting questions were more around - how quickly? for how long? would the original rankings come back? if so, better or worse?

I was wondering whether it was Econsultancy's trials and tribulations that prompted Matt Cutts to uproot his site...