I have checked my websites position using hidemyass as well as http://www.diagnosticoweb.com/ but my sites position vary so much, why is this? Which is the most reliable?
I think hidemyass is a proxy and based on its servers Geo-Location google is displaying results of that country in Google Search. Same applies to the other one..
Yes, SERPs depends upon the geo location as well as your interest (i.e. what are your searching habits, tracked down by cookies and results vary based on your frequent searches)
Its called the "google dance" google has a certain type of algorithm.. just keep gettig backlinks to your site it will eventually settle in a good position..
I m also facing this kind of problem...my all keywords of main site is now dropped very poorly. I am not able to find the related answer for this because from the last 2 years we are top of the charts.
Yeah the search results vary from small to big - based on geography, past search history (cookie), ISP etc.
That phenomenon is still unclear.. Google also likes to present search data as soon as you type the query in google thats why when you are in uk and type google.com you are supposed to be taken to google.uk (which is its nearest dc) But if you have set your browser default url to Google.Com then when you open the browser in UK you also see Go to Google <countryname> link below that typical google Textbox.. Click on dat link for localized searching. But results are not always same if you type Google.Com in USA and Google.Com in India/UK or any..Others factors also come into practice..