I took a look in the online guide today, and was amazed.

Prime and MaoriTV EPG data is now available on the TiVo!

It is only a few days in advance rather than the full 2 weeks, but this is still a big win. Finally, I can bother to watch Prime again (and being able to skip the excessive advertising helps, too.

Props to TiVo (and Sky & MaroiTV, I suppose) for getting this working.