I've been studying Solaris 10 and 11 recently because I'm aiming to acquire a SCSA. It is not surprising that the most popular flavor of commercial Unix is losing ground.
One should not have to register/login to download Solaris or packages for Solaris. Get with the times, Sun. Solaris is supposed to be open source. That's means everyone should get easy access, no questions/logins. I'm talking about anonymous ftp, rsync, and bittorrent. What is more important? Solaris's statistics or relevance.
It's not completely horrible. It does figure out dependencies. It's essentially just the equivalent of rpm or dpkg though. There is nothing like yum or apt-get on Solaris 10 or 11. This is a problem. Installing and updating software is a chore, especially installing Solaris Companion software, like vim on Solaris 10. The solution to this is easy. Sun needs to integrate the IPS system from OpenSolaris into their commercial versions.
Why are Solaris administrators still using plain Bourne shell by default? Sun, be nice to your sysadmins and give them tab completion and command history by default. Bash is plenty mature to be the default shell. I cannot see any serious admin using Bourne, if they don't absolutely have to. Sun should see this too.