The solution to the known problem is more or less "don't use them" (ie, punycode them). It's still a pretty crap situation, it'd be nice to have but if we actually use them in a nice manner, it opens Pandora's Box.
They show up properly for some TLDs, those that have a policy of not allowing confusing/pointless characters. Far as I can tell though, you can't register names like the following (due to TLD restrictions).
http://☁→❄→☃→☀→☺→☂→☹→✝.org/