Will there be available stable version of QGIS 1.7.4 in Ubuntu 12.04?
Version 1.9 is working fine at the moment, but as it is unstable currently, don't want to risk it with my work.
The UbuntuGIS-Unstable repository (https://launchpad.net/~ubuntugis/+archive/ubuntugis-unstable) currently has QGIS 1.7.4 for Ubuntu 12.04. Despite the "Unstable" name, the packages are typically more stable than the QGIS unstable repository.
If you really want to avoid unstable versions of the packages, just be vigilant when you run updates, and keep an eye out for 12.04 packages to arrive in their stable repo (https://launchpad.net/~ubuntugis/+archive/ppa). IIRC, there was a few months' delay in the stable PPA after 11.10 came out.