I put together a table that shows the assignments made by IDNA2008 and IDNA2003, respectively. I would urge people to review these for problems before Stockholm.

The file is at: http://macchiato.com/idna/idna-info.html

There are plaintext versions in that directory also. The tab and html versions allow copy and paste into your favorite spreadsheet for comparison, so that you can filter and sort by different values.

Key

Field	Contents	Comments
1	difference status	w = warning, X = ambiguous mapping, blank = no problem
2	codepoint or codepoint..codepoint
3	character(s)
4	idna2008 status	PVALID, CONTEXTO, CONTEXTJ, REMAP, UNASSIGNED, DISALLOWED; REMAP if the code point is DISALLOWED but has a mapping
5	idna2008 mapping	"n/a" unless REMAP "delete" unless non-empty
6	idna2003 status	"~" if same as idna2008 status
7	idna2003 mapping	"~" if same as idna2008 mapping
8	script
9	general category/ies
10	description(s)	name(s), or designations for those that aren't characters

Please let me know of any problems!

Firefox Characters

Here is the set: http://unicode.org/cldr/utility/list-unicodeset.jsp?a=[\u01C3\u02D0\u0337\u0338\u3033]

My take is that all of these are legitimate characters.

Item	Example	Comments
\u01C3	aǃb vs a!b	typically identical, but ! isn't allowed in domain names anyway.
\u02D0	aːb vs a:b	similar, but not the same appearance. Could be confused with : used in URL password or port, so UIs should probably warn.
\u0337	a̸b vs a/b	not really confusable because of positioning
\u0338	a̷b vs a/b	not really confusable because of positioning
\u3033	a〳b vs a/b	not really confusable because of positioning.
\u05F4	a״b vs a"b	similar, but not the same, and " isn't allowed in domain names anyway.