At my company we've been developing software for solaris for over 10 years. We develop and do some testing on solaris workstations, without having root privileges. This has been working fine for a long time. If you need some new software installed, it is still possible to do it without being root and if you need something installed for everyone, it is better to ask the admins to install it, because they will also maintain it for you.
Lately we've be using Windows as well. Every Windows developer machine comes with local admin rights, because it would be too difficult to get anything done without it.