Since MySQL 5.5 was declared stable in December last year, I regulary receive e-mails from people asking when it will get uploaded to Debian. The good thing is that the initial conversion from automake to cmake has already been done by Clint Byrum from Ubuntu, and we are going to use his work as a basis for our packages. The not so good thing is bug #59078, an issue in libmysqlclient which breaks ABI compatibility. According to Lenz Grimmer from Oracle the MySQL upstream developers are already looking at it.
I am still not sure if it is a good idea to upload MySQL 5.5 in the current state to experimental, but I am definitely not going to upload it to unstable until this issue is fixed.
Update: I just had a conversation with Matthew Montgomery from Oracle, who told me that the SONAME of libmysqlclient will get bumped in 5.5.10, which is going to fix the problem.
I am still not sure if it is a good idea to upload MySQL 5.5 in the current state to experimental, but I am definitely not going to upload it to unstable until this issue is fixed.
Update: I just had a conversation with Matthew Montgomery from Oracle, who told me that the SONAME of libmysqlclient will get bumped in 5.5.10, which is going to fix the problem.