UI layout in code can be a pain because you can't see what you're doing until you do the compile-install-run which can be 30 seconds. That's a hefty amount of time if you're just tweaking one visual element and need to run through 1-10 possibilities.
Normally I would agree- ALL my iOS apps are done in Interface Builder. But if you add more than 50 PNGs to an Android/Eclipse project, the iteration cycle is well over a minute long compared to a 5 second recompile. That's not counting the slowness of the Android emulator (hardware was faster for debugging for me)
