The replacement for the Hubble is scheduled to launch in 2013. The James Webb Space Telescope will have the ability to see further than Hubble and feature mirrors over 20 feet in diameter. Its sunshield alone is bigger than a tennis court. This new telescope will be situated about a million miles from Earth, putting it beyond our current ability to service it. However, scientists have taken the problems with Hubble into account and have made the appropriated modifications to allow the telescope to self-correct.
NASA: http://www.jwst.nasa.gov/
CNN Video: http://www.cnn.com/video/data/2.0/video/tech/2009/02/11/eoj.hubble.replacement.cnn.html
