How do you decide which blogs to follow?

This follows on from my last post on blogging. I'd be really interested to know what makes people decide to follow a particular blog. There are an awful lot of them, from the brilliant/funny/inspiring to the weird and the downright mad (I've just happened upon one of the latter, and can honestly say I have no idea what the blogger is writing about). It's impossible to be a "follower" of every blog that takes the eye, but the ones I choose are:

Not too long. Very lengthy posts take a lot of time to read, and while they may be good to dip into, it's hard on a regular basis.

Funny. Entertaining. Light relief.

Literary. About books and writing, especially writing (this for obvious reasons).

Zany. I love eccentric people (a certain layabout cowboy springs to mind)

Varied. Blogs that concentrate on a single topic can be tedious.

Horsey (Titch likes to feel involved).

What about you? And how do you feel when you gain or lose followers? Honest answers, please!