What is the difference between odexed and deodexed roms? Which is the standard (stock) roms that ship use?
ROMs are typically released in deodexed form because they can be themed and modified fairly easily, whereas theming/modifying an odexed ROM is basically impossible (at best things would crash like crazy). Some people also choose to release their ROMs in odexed versions for people who would prefer the performance gains.
Most of the stock ROMs I've seen are odexed, I assume because the carriers/manufacturers want the performance boost. They also don't have any kind of official theming methods, so they probably don't care if you can't change the colors of your status icons or your system text or whatnot. Plus they have the advantage of knowing what device they want their system to run on, so they can pre-compile the
Edit: Since I just realized that I was not very explicit about the difference here - an "odexed" ROM is one where the apps have been precompiled, and thus contain associated
A .dex (dalvik executable) file is basically similar to Windows' .exe files (except in Dalvik VM's language, instead of compiled code). Basically, .odex (optimized dalvik executable) and deodex (de-optimized dalvik executable) relates to how resource files are handled in the applications. The .odex is a .dex file that have been optimized by the dexopt program: http://www.netmite.com/android/mydroid/dalvik/docs/dexopt.html