Are my permissions for /usr/local/ correct? I’m using HomeBrew for my port needs (seems a bit “cleaner” than MacPorts).  

I can install without sudoing (which is great), but the man linking step seems to require it (/usr/local/share/man/man3 is owned by root).
A guide I found suggests I recursively chown /usr/local by doing

sudo chown -R `whoami` /usr/local


Is this safe…or is it a Bad Idea™?

Also: are my permissions correct?

$ pwd
/usr/local/share/man
$ ls -lah
total 32
drwxrwxr-x    8 root  staff   272B  4 Set 11:02 .
drwxrwxr-x    9 root  staff   306B 10 Set 11:27 ..
drwxr-xr-x    3 root  wheel   102B  4 Ago  2009 de
drwxrwxr-x  163 root  staff   5,4K 10 Set 11:27 man1
drwxr-xr-x   11 root  wheel   374B 10 Set 11:27 man3
drwxr-xr-x    7 ago   staff   238B 10 Set 11:39 man5
drwxr-xr-x   11 ago   staff   374B 10 Set 11:39 man7
-rw-r--r--    1 root  staff    13K  4 Set 11:02 whatis
I use Homebrew too and can confirm it's totally safe. Quoting the Installation page on the official Homebrew FAQ:


  Do yourself a favour and pick /usr/local
  
  
  It’s easier
  /usr/local/bin is already in your PATH.
  It’s easier
  Tons of build scripts break if their dependencies aren’t in either /usr or /usr/local. We fix this for Homebrew formulas (although we don’t always test for it), but you’ll find that many RubyGems and Python setup scripts break which is something outside our control.
  It’s safe
  Apple has conformed to POSIX and left this directory for us. Which means there is no /usr/local directory by default, so there is no need to worry about messing up existing tools.
  
  
  If you plan to install gems that depend on brews then save yourself a bunch of hassle and install to /usr/local!
  
  It is not trivial to tell gem to look in non-standard directories for headers and dylibs. If you choose /usr/local, everything “just works!”


I'll just add that doing things as root is a very bad idea, so chowning /usr/local not only seems reasonable to me (it's not a system dir on OSX), but sane.

Your permissions are not correct (yet). Just run the command you listed and you're gonna be fine.

If you have other problems remember, the brew doctor can help you!