This reminds me of spread.us, which was build by the guys at The Next Web. It's now for sale on Flippa. I believe they found it was hard to make people pay for this service, but perhaps @boris or @patrick can answer this themselves ;)
@bramk looks like it didnt sell because it didnt reach its reserve, asking price was $9k..
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Hunter
After signing up with TweetSquad, you’ll need to recruit people to your squad; basically, your squad will likely be comprised of your most loyal supporters on Twitter – from fans or consumers who like you to personal connections, like friends and family. In joining your TweetSquad, each of those users will agree to give you the ability to retweet one of your tweets to their followers one time per week. What this means is: if you have a really important message/announcement/link for which you want to maximize click-throughs on Twitter, you simply have to select that specific tweet and use however many of these retweet credits are available to you, and then that selected tweet gets automatically retweeted through the accounts of those in your TweetSquad.
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What I don't get with this product is that if your fans / friends / family want to support you, they don't need to give you access to their twitter accounts. They'll gladly RT your messages. For free.
I wouldn't be really ok to let someone tweet something to my followers without my "pre" consent. If you want me to "broadcast" your message, just ask me, talk to me, do not use me as a tool.
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