IE and Firefox Results very different

[surfing-mtber]

I know this issued has in part been discussed before, but would anyone have any idea why the results for search in Google usng Firefox is very different when using IE?

Take one of my sites:
Antique Maps Online - Friendly Service - Family Business
Using the term 'antique maps'

No. 12 using Firefox
No. 53 using IE

In contrast: Antique Paintings Online
Using 'antique paintings'

No. 1+2 on FF
No. 1 on IE

Have tried signing in and out, and clearing temp files, cookies and history in both and it makes no difference.

Advice appreciated.

[DellaEmery]

It may be due to local search like google . uk from google . com. have you checked whether the both have same .

[williamc]

Nowadays it can be several things, personalized search, different useragents getting different datacenters, local search parameters being used....