It is a super site, hosted by an English fellow named Doug Ellison. Paid for by donations from grateful members (I gave a bit as well). He asked for some donations a while back and in a few days got enough to run the site for the next couple of years.
THE site for following all missions of unmanned spaceflight. JPL scientists and engineers post there as well, among them one of the mars rover drivers and the guy who designed the entry, descent and landing system of the rovers and is now working on the super rover they will send to Mars in a few years' time: Curiosity.
Some of the members who play around with the raw photos the rovers send down are the best in the business, getting front pages on Aviation Week regularly.
It is fantastic that the raw images from various space missions are being posted real-time on the web so everybody can have a first look together with JPL scientists. Reasonable enough, given it is paid for by tax dollars, but still amazing.