Hi, I've noticed that I get different results if I use google.com from different browsers. I've started with a 'site:" search and I got 178 in IE and 109 in Firefox. Checking my google referrers for about 2 weeks I keep seeing result pages from where the visitor came but I can't seem to find my sites in SERP. Since the vast majority of visitors are from the same region like me, I couldn't understand the difference in SERP. Could be the fact that I'm using Firefox and they're using IE?
Do you have a gmail account? Are you always signed in if you do? Because it COULD be filtering your results with search preferences. I think this was happeneing to me this week... Though personally, I would go for the datacenters answer. It just depends on which center you get directed to at the time. Empty your cache in both browsers and see if you get the same results if you do the search at the same time.
I do not use gmail. The point is that in firefox I have set google to display 30 results per page and very often I do not see myself in this Top 30 and, probably my visitors, like most users, have the default 10 results per page.
I was hoping to find other people in the same situation but perhaps I'm an isolated case (who knows, perhaps some different settings in IE and Firefox).
Try using a specific data center. Try going to http://64.233.187.104/ in both browsers and then test maybe?
With http://64.233.187.104/ I get the same results on both browsers. If I switch to google.com it's a different story...
That means that it is down to the underlying datacenters being different. All that's happening is that when you connect to www.google.com you are being routed to different machines for your results..