1- GrandCentral's Web button is different from Skype's. When someone clicks on it, the service calls that person's number (mobile or landline) and your GrandCentral number then connects both of you. There's no need to be in front of your PC. PhoneGnome is doing something similar as well as Jaduka;
2- If you're a GrandCentral user, you can now embed/share any voicemail that you've received on a web site. I can only think of a bad use of this feature ie embarrassing someone that has left me a nasty voicemail!
3- The new web site should be live by next Monday. It adds a Google Map mashup that indicates on a map your caller geo position as well as an upload manager for ringshares (the ring callers hear which could be any song or sound you want). Lastly, the way GrandCentral is displaying all of your incoming calls can save you lots of money if you're a T-Mobile subscriber with myFaves option. Simply add your GrandCentral number as one of your "Fave 5" and all the incoming calls you receive will then be free... Cool hey?!