What "common" format to export for other 3D apps?

Folks,

I am a big fan of the TurboSquid model repository. I am pretty new to Blender but want to share some models I have built with the world. What is the recommended/best data format to export a blender model so that it may be consumed as cleanly as possible in other applications.

I see that Blender has a goodly array of imports and export formats supported. Is there one which is a defacto common standard and exports/imports well from Blender?

.obj/.max/.3ds and ofcourse .blend lol.

.obj - yes. This would be my particular choice. quad and tri
.3ds - yes. I believe this only supports triangulated geom
.max and .blend are both proprietary and for the most part supported mainly by their own app.

I third the OBJ,

I only suggest using 3ds, if your destination application does not support OBJ, Triangles are totally evil and should be avoided at all costs.