The service has been getting plenty of buzz around the web, and rightly so. Its main drawback is that signing up for an account required you to pick a new phone number, and then pass that number around to everyone who’s likely to call you in order for it to be effective. That is no longer the case, however, as Google has now enabled users to keep their existing phone numbers and get some of the features Google Voice offers.
Going for this "lite" version will basically give you access to international calling and Google’s voicemail service -- including the ability to have them transcribed and placed online for later review or sharing with others. Meanwhile those using the Google-provided number will retain the full array of features that come with the service. The company has published a help page explaining the differences between the two options.
The service is still not widely available to the public. If you're not yet using Google Voice, you can request access here or ask a friend with a Google Voice account to send you an invitation.