An excerpt from an AP update on Google’s video etc. plans:
Google, the Internet's search leader, has been adding more bells and whistles to Gmail as part of its effort to gain ground on the longtime leaders in free e-mail, Yahoo Inc. and Microsoft Corp.
Video chatting has long been available through the instant messaging services offered by Yahoo and Microsoft, but the feature isn't available in their free e-mail applications.
Although Mountain View, Calif.-based Google has been making strides since it began welcoming all comers to Gmail early last year, it remains a distant third with nearly 113 million worldwide users through September -- a 34 percent increase from the previous year, according to comScore Inc.
Microsoft's e-mail services boasted 283 million worldwide users, up 13 percent from the previous year, while Yahoo was a close second at 274 million, an 8 percent gain, comScore said.
Unless I’m missing something, this perspective is partially inaccurate; real-time communication tools such as voice and video are associated with contact management and presence awareness – services which may be integrated into multiple contexts, including email, but are ultimately more IM- than email-centered. So Google is in catch-up mode in this context, not leap-frogging (e.g., Windows Live Hotmail does the contact/presence-augmented email => real-time communication trick as well).