I don't know if Adobe will give a list, but the ones I can think of immediately ...
- Just stops working for some people for no apparent reason
- Refuses to turn pages for some people (the page marker moves but the page doesn't)
- Fails to recognize some devices that v1.7.2 does
- Will not work with some Sony eReader devices when using Overdrive library books (That's the reason I mainly use 1.7.2)
- Doesn't work reliably on XP
- Sometimes gets in a curious semi-authorized state (I think this may apply to 1.7.2 as well though)