It seems Google are having an early spring clean of their applications and projects. As a precursor to Google making staff cuts they have started to shut down a number of projects. Google Video is the first of these - something which has become redundant since Google bought YouTube. The services did get merged, but the Video team is no longer required, nor is the separate project - so it's been culled.
The next one, Google Mashup Editor was designed to enable users to create mashups of services quickly and easy though it never really took off and wasn't as popular as Yahoo's "Pipes".
Jaiku is a pretty obscure one, it was a start-up that Google bought out early on before they could release a beta. The idea behind it was very similar to the status updates you now see on many sites such as Facebook and Twitter.
Dodgeball is one that does have a fair sized user-base, which is why I find it odd that Google chose to close this one - especially in light of recent start-ups such as Brightkite. With the advent of the iPhone, GPS, and micro-blogging it is one that if marketed correctly could have really taken off, but no, Google messed up with this one.
Google Notebook's intention was to enable users to take clippings from any page and have them available on any machine that is signed in to Google Notebook with your account.
Google Catalog Search is one that has already gone, with it's functionality absorbed into Google Base.
