Love Rabbit Hole.   There are at least 3 CTs with productions opening this season and it's on the list of considerations for my CT for the 2009-10 season.    It's a wildly popular drama like Proof was when rights first became available for CTs.

Don't know Butterfingers Angel, but Rabbit Hole is a wonderful script.  I don't think my audiences would go for a full production, but it is on my short list for at least a staged Reading.  However I myself will probably stay clear, with a 5 year old son, the play just hits a little close to my inner fears. 
If you have not read it do so, it is wonderful just to read.
To all those who are listing it as "high on the list" PLEASE let the rest of us know how it goes over with CT audiences.

Rabbit Hole is a fantastic script!  One of my favorite CTs here in San Diego mounted a production this past spring.  I know it was a multi award winner...although I don't have a lot of insight into Box Office.  The performance I saw was well attended, and I believe (I think this is what I remember) they saw a typical "drama" audience.  Nothing like putting up a Simon...but not a money loser either.

While I do not know anyhting about either of these shows, I would volunteer a resource I use when looking for information about a particular play.  Try looking both of these shows up on google books (books.google.com).  Go to google books type in the name of the show and or the author.  If the play comes up on your search results, look for a line that says 'limited preview'.  Click on that to pull up excerpts from that particular show. I have been able to get a lot of information about a script using this.  Including, but limited to, who holds the rights, cast details, and technical notes.  I did do a search and both of these shows have limited previews.  Hope this information is helpful.