I think it is always a nice idea to get another cat. The two can keep each
other company when you are at work, on vacation, etc. It doesn't matter what
the sex is. I have to females for example that get along pretty well. But of
course if you are pressured into balance male/female is always good too.

I've always heard it's best to have them in "pairs".  One of the shelters
vet techs tells me that - not sure why.  I've only got seven......of my own!

JoJo
http://home.comcast.net/~zookeepr/fosters.html

If you're in a situation where you are thinking of getting 2 cats, why not see
if there are 2 cats already waiting to be adopted (who are already used to one
another). It's great when 2 cats don't have to be separated!  Maybe a mom and
baby or 2 siblings ready for a loving home!  Good luck.

Check with your local shelter. Much of the time, shelters will have "bonded
pairs" available. These are cats that likely were raised together or have
lived together for a long time, and separating them can lead to depression,
lack of appetite, illness, etc for the individuals. Bonded pairs usually
take quite awhile to get adopted, so I'm sure your local shelter would be
thrilled that you're interested in two!

A benefit of adopting a bonded pair as opposed to two cats strange to each
other is that you do not have to deal with introducing the cats to each
other on top of bringing them into a new home. These cats will help keep
each other calm while they're learning the ropes of their new home, and
they'll keep each other busy while you're occupied (sleeping or working or
whatnot).