Just in case it it any use to anyone, there seems to be an issue with McAfee SiteAdvisor in conjunction with IE7. What seems to happen is that clicking on any (non-sponsored) link in the results always links to the last result on the page (which makes it seem like there might be some malware hijacking going on, which is a tad disconcerting).
I have been running an old version of McAfee SiteAdvisor (v126.96.36.19961) with IE7. By a process of elimination (i.e. disabling / uninstalling add-ins), I determined that the issue lies around SiteAdvisor. Upgrading to the latest version (v188.8.131.52) seems to resolve the issue.
Note that disabling the old version of SiteAdvisor did not eradicate the issue - I had to uninstall the add-in altogether.
BTW, I imagine that the issue with the old version of SiteAdvisor has been exposed by a recent update to IE7 or something like that.
If anyone still has issues after applying the above, would be interested to know.
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