It will be a sad day tomorrow as GeoCities is closed down for good by Yahoo. Thousands of websites will disappear offline tomorrow and along with them all the links pointing to other sites. Imagine if your website had more than 50% of its incoming links coming from GeoCities. Is your Page Rank going to suffer in the coming days once those links no longer exist? Quite possibly!
It’s difficult for anyone to know whether this will have any impact on their search rankings. I’ve measured over a hundred links to one of my sites from different GeoCities sites so I’ll be keeping an eye on it and hoping those site owners move their pages elsewhere. Of course, many GeoCities sites won’t be resurrected elsewhere as they are often dead and haven’t been updated in ages so from tomorrow those links are gone. What impact all this will have on SEO and search engine rankings will play out over the coming weeks as Google and co. re-index sites and take into account the missing links.
More importantly than any inbound links though is the fact that a piece of internet history is dying. Jeremy Keith sums it up well so I suggest you read his post on the subject.