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I confirm @akrid 's answer. It's 100% powered up. It signals that the author believes in the post or at least it's their best post at that time. Some people who don't post a lot may have this symbol next to their post bc they don't mind using that much of their voting power at the time since it'll regenerate by the time they're ready to post again. It was a good question. Gave ya a follow :)

Thanks @showoff! I didn't know you could adjust those settings.

I was also wondering about that. Thanks for your question!
b.b.