In recent weeks Twitter has been plagued by follow-spam from thousands of ignorant, immature people blindly following Scoble's prescription for Twitter "success." The ethos was entirely quantity over quality, and quite impersonal -- sure doesn't sound particularly community- nor conversation- -oriented now, does it?
I follow about 250 people more than follow me. I also follow far too many people to be "intimate" with many of them through Twitter. But in my book, that's FINE -- Twitter is transient. It's a firehose -- embrace it, but don't drown yourself!
I could care less how many people you follow, how many people follow you, if you're INTERESTING. If you're engaging in CONVERSATION, if you're sharing thoughts and ideas, I say RIGHT ON.
If you're one of these mass-adding Twammers (Twitter-spammers) then I say: die in a fire. Slowly. Perhaps roasted on a spit.
Follow people because you find them interesting, not because you're trying to play the numbers game. And, don't use Twitter as your personal ego-horse or mouthpiece! Such use is pretty obvious, and not desirable in the LEAST.
Personally I think the two best ways to find new people to "follow" are 1) eavesdropping and 2) outside sources. If you see someone having an interesting conversation with someone you already follow, FOLLOW THE NEW PERSON. Also, if you have outside contact with someone -- whether personally, or through their blog or another social network, then again, by all means FOLLOW THIS PERSON.