Back in the days of Grand Central (Google Voice pre acquisition) they offered a plug-in for Microsoft Outlook that allowed you to call contacts. This made and still makes perfect sense considering the number of people that spend a large portion of their day in Outlook. Yesterday, Google announced users will be able to make calls from GMail which makes sense considering the history of outlook.
The interesting feature is the ability to receive calls on your Google Voice number in GMail. This functions like Google Video chat does in Gmail today, but it does not remove the desire for a desktop client. The feature is rolling out to user over the coming days. If you are a Google Voice user you should also download the app for your mobile phone or bookmark for your iPhone.