[alimj]

I think the key to emailing cold is that you have to make it plausible that the other person can get something achieved for you in your connection. If you approach genuinely but don't know what you want out of the connection, then you're making it a risky endeavor for them in giving you their time. (and ain't nobody got time for that)

[laurenstill]

I don't remember where I read it, but ask to interview them, either for your blog, or something else. I've done this a few times with people I considered reach connections. Two years later, they are some of my closest allies.

[mvkel]

Absolutely. In other words, they need to be convinced they'll get something out of the conversation, where "something" is anything from a simple ego boost to advice on something you're really good about that he/she isn't.