Good idea to login with twitter?

I'm a student working on a small website/project for practice using PHP and learning to use API's. It's essentially a digg or reddit-like website, where users submit an article and others can upvote and comment on it. So far, I've had no way of restricting users to a single vote per submission.

I thought it might be a good idea to implement "log in with twitter", and associating whether a user has voted on开发者_运维技巧 something before with their twitter ID (or ID number). If the ID isn't recognized (they haven't logged onto my website with twitter before), their username would be added to a SQL database and their username would also be recorded in a seperate database for each question that they agree to.

My question is: Is this a good idea? Are there any reasons that this wouldn't work in the long term? I haven't had much experience with web development, so I don't know if I'm making some sort of security mistake or being incredibly inefficient.

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There is a better method, use OpenID like this website. I don't think it will be too hard.

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Not everybody has a twitter account, and you can't obligate to create one for login in a specific website.