[SOLVED] Some interesting "bug" that i think is worth sharing...

[menakite]

Try to determine the user (UID) xbmc.bin is running under, it should be "xbian" and its home directory should be /home/xbian/.xbmc.
If all this is true, try:

Terminal

sudo chown -R xbian /home/xbian
sudo chmod 755 /home/xbian /home/xbian/.xbmc

It is suggested to allocate 112 MB to the GPU on Model A/old Model B with 256 MB and at least 144 on newer Model Bs (512 MB).
You can limit resource usage by lowering the GUI resolution to 720p, using a skin with "simpler" textures (stick with the default Confluence skin, or try Amber), etc. However, this is very setup-specific - different audio/video codecs may require more, or less, memory on the GPU: you need to find out the minimum required for your setup by just trying to lower it a couple times per week (to check if it's stable and no glitches appear).
Until you see "ERROR: ... OMX_ErrorInsufficientResources ..." in your xbmc.log, your gpu_mem is okay.