Well, there are two schools of thought on that one. "Yes", and "No" :-) I tend to fall into the "No" camp, and I'll try and explain why on this page.

There are two possible sources of worry over being located. Either you've got 'Authority' (in whatever manifestation) after you or you're worried about spammers (sorry - Internet direct-marketeers. Spit.)

If you've got 'Authority' on your case, there's nothing here that they don't already have access to, and in fact they'll know a lot more. They'll know exactly when you logged on (if you're DHCP or fixed-ip, modem or leased-line), and probably even have a packet-log for recent stuff. Face it. They've got you.

So, ignoring 'Authority', we're left with spammers. There are a few points I would make as to why the site isn't the panacea for spammers that some would believe...

• Spammers / Internet marketers already have access to far more-detailed commercial databases than I could realistically provide. There are a few companies (quova,maxmind,others) who will sell (at not a huge cost) their DB to anyone. They have hardware at the major internet routing nodes doing this automatically using statistical analysis of traffic between already-known places. Hostip was an attempt to level the playing field, not provide a vehicle for spammers.
• Spam by its nature is (currently, at least) a mass-delivery "shotgun"-type approach. They don't care where you are, what sex you are (which is surprising considering most of the products!), what age you are, etc. etc.
• Should spammers ever move to a more 'sniper'-style delivery using hostip to locate localised businesses, I would shut the site down. I consider them to be the scum of the Earth, too. The database is surprisingly fluid, within a few months it would be pretty much useless apart from huge institutions, which can probably fend for themselves. For a 'sniper'-style approach to work, I'd expect them to need more info than what geographic area you live in, as well...
• Hostip only locates you to your city. You are still reasonably anonymous within a city of 100,000 people! If you're in a small township, you're almost certainly on a DHCP circuit, and the system won't cope well, anyway. At the moment, hostip will just respond with the last location to register any given IP, which on a widely-distributed DHCP network could be hundreds or thousands of miles away! I think both large and small are covered here...
• Hostip doesn't allow reverse lookups (what IP addresses does this city have allocated to it) even though it'd be a trivial operation. This is an attempt to block abusers, since I can't think of any use for that information.

I made this site up, mainly to see if I could, and to see if people would band together to collectively create something like this. It's looking good so far :-) One of my goals is a graphical 'traceroute' program, and a webstats program that lets me see where my visitors came from on a globe... just because I'm curious.

If you feel you have to pollute the DB, then by all means do what you feel is right. It's sort of disappointing given the work I've put into the site, but it'd be naive to think that everyone has put in their correct location.

For what it's worth as a final thought, I don't think hostip contributes in any way to spammers targetting you. I think other agencies (govt,police,your ISP) have far easier and more-effective methods to track you, so it's no use to them either. It's just a "cool tool" for geeks like me :-)

Hostip.info is an open project. There are many mashups, plugins, and APIs to choose from, all contributed by the community as part of an ongoing open-source effort. The most important resource, obviously, is the data, which is completely free and also owned by, and contributed to by the community. The Hostip.info operations (hosting and bandwidth costs, etc) are sponsored by Net Industries, LLC.