These changes have been oscillating in and out here on queries using browsers ID'd as English language on machines running English OS's for a few weeks now ..apparently over the weekend they decided to make them sticky..previously they were being served in our night time ..after 22.00 hours..til next morning around 08.00 to 10.00
Queries run using French language systems set to French ID and French as preferred language have been oscillating around the same times and are continuing to do so ..but I think they will stick at what many posters here don't like.
That may explain what crobb305 is seeing ( that adjustments can pay off )..
cwnet's post is IMO of particular relevance..as is Google's reference to using user feedback rolled in ..as I mentioned in another thread ..how does it look to an average surfer ..how do they feel about your site..is more important than how you feel about it ..again the preview tool was a precursor to the user assessment being important ..
You are not the customer ..Google is interested in how the surfer feels and reacts to your site ..and how satisfied the advertisers are ..
Not excusing them ..but it makes sense ..and has done so for a long time ..if we cant survive as we are ..we must either evolve or die.