There’s been an XDA thread for a while now with a bunch of different 2.3.4 GTalk rips with varying tweaks and installation methods, but here’s the best and easiest if you’ve got root and either Android 2.3.3 or 2.3.4, stock or custom, front cam or no front cam, just need root. Got root?
Download the highly-acclaimed [root] Talk 1.3 Installer from the market, hit the backup button just in case, then tap the button to download and install the freshest version of the default recommended package (xilard) which is both likely to work and, unlike with Apple devices, you can use it over wifi and cellular for however long it takes you to lose interest in this silly video chat thing. So silly.
Not recommended for AT&T subscribers… :P