It has been a while yes. One of the reasons we haven't made an explicit upgrade to Ice 3.4.x across the board is that the two most common Linux distributions don't come with this version of Ice. ZeroC kindly provides RHEL/Centos Yum repositories for several versions of Ice (including 3.3.x) as it doesn't come with the distribution and Ubuntu, for which Ice is included is still at 3.3.1.
The odd platform out really is Mac OS X, and Glencoe Software has kindly provided a complete pre-compiled binary Ice 3.3.1 distribution that is linked off the UNIX platform install page.
All this said we do intend, with OMERO Beta 4.3.0 to support Ice 3.4.x and potentially both 3.3.x and 3.4.x Ice distributions. If you want to track the status of the upgrade in Trunk you can do so here:
http://trac.openmicroscopy.org.uk/omero/ticket/1274