On topic, as I have mentioned before (although I of course realize this would take some work), I think it would highly beneficial to have a very clear indication (suitable icons or similar) in the module repository to show which versions of Xoops it compatible with, similar to what they have on joomla.org (although I must admit that using my sites from 2.3, upgrading to 2.4 and then 2.5, I haven't really encountered many, if any, compatibility issues, I guess I've been lucky).
Regarding XoopsPoll, v 1.31 works with 2.5 and version 1.32 (which Mamba is working on) is exclusively for 2.5.