Found this originally here at about.com who links to London2012.com. Though this is a web-cam photo there is no direct link provided to the web-cam itself.
From London2012: "...Progress on the site is well underway with construction starting in July 2008, two months ahead of schedule. During the Games the Aquatics Centre will include a 50m competition pool, a 25m competition Diving pool and a 50m warm-up pool. ..."
See renderings here for the new London Aquatics Centre.
Other venue web-cams: [Link]