Had it been my call I wouldn’t have risked the astronauts. Hubble had already given us well beyond our moneys worth, and now other orbiting observatories such as the Webb are carrying the main science burden.
That being said, the rescue mission having occurred anyway I’m very pleased we will get several more years of Hubble pictures. Especially as it seems this isn’t the sort of administration now that would fund a proper replacement.
The James Webb Space Telescope (JWST) will be a large infrared telescope with a 6.5-meter primary mirror. Launch is planned for 2014.The Hubble is a one of a kind, and will be for a good while. It'll never be replaced, because no one will ever want to spend the money again.