Copyright (c) WebsiteNeighbors.com. All rights reserved.
It's a good idea to scout out IP neighbourhoods. If you're buying a shared hosting plan, you want to know if your IP is shared with websites that may be blacklisted for spamming, or related to porn or online gambling and possibly penalized by Google. Know your IP neighbours.
It's also important to check out your competition. When checking out competitors in your niche, wouldn't it be nice to know what other websites they control, in case they are using them to create link networks, generating free backlinks and boosting their own SEO value? Of course it is!