I use it mainly for two reasons. First it is a good call filtering service. You know how it was popular to give out a secondary email address to people you didn't want to get spam from? You can basically do that with Google Voice because if the caller isn't on your contact list, you can have it ask them their name and then when you answer it tells you the name and gives you the option to send to voicemail (you can even listen to them leave the voicemail) or answer it. I used that feature a lot when I was car shopping! The second feature I use it for is to replace my voicemail. It gives you a lot of voicemail options such as visual voicemail, an inbox you can delete/archive/etc... The last thing that it's useful for, that I don't use it for too much, is it can connect to multiple phones. Meaning, you never have to change your number again. Your Google Voice number should always work, as long as you setup your new phone. I don't give out my GV number to friends though because it can't handle MMS messaging.
