~/.ssh/config is one of the simplest, most useful features I use on a daily basis. It would be easy to accomplish much of it's behavior even if it didn't exist (bash script for each account@host), but it wouldn't be as elegant.
The config-aware shell completion is especially cool.
Interestingly enough that ticket is about preserving and/or following - I would be happy with ignoring so it doesn’t end up in an infinite loop - as it stands a self referencing symlink with files in the same directory will result in either your disk filling up, your inodes filling up, or a maximum bested paths error (assuming your FS has such a thing).
Edit: and until the ticket you just linked, I assumed scp and cp were intended to be close equivalents, given the whole ending in ‘cp’ thing.
The config-aware shell completion is especially cool.