Hi10P (also called "10-bit") is a profile of the h.264 video codec. It has recently become popular in the anime scene for video encodes. The first stable version with Hi10P support is XBMC v12 (Frodo). As of XBMC v13 (Gotham), XBMC will automatically use multi-thread (multi-core) software video decoding for Hi10P videos, allowing for better performance on low-end processors.
Hi10P won't work on most ARM or even some Intel ATOM processors. Hi10P can't be hardware decoded (which is to say, no one currently makes hardware decoders for them and no company plans to add Hi10P hardware decoding in the foreseeable future), which is what a lot of low-power devices require for smooth video playback (such as the Raspberry-Pi, Android, ATOM processors, and some AMD APU systems). Thus, Hi10P requires CPU/software decoding.
A safe bet would be at least a Core 2 Duo/Celeron G530 processor (or equivalent AMD) or higher.
Some (most?) ARM processors are not powerful enough to software decode it, and no hardware decoders exist for it. As faster ARM CPUs come out this will get better, but don't expect miracles from the average Android box.