If she's really that bright and academically advanced, putting her ahead one grade is not really going to make much difference at all. If she's bored now I will betcha ANYthing she will still be bored in the higher grade too, or will soon enough.
In terms of emotional/social maturity, remember it is not just how she is now, it is whether she will be comfortably up to speed with the older kids *for the rest of her school career*, since it is awfully hard to undo a skipped grade.
Personally, unless you know something else than posted in your blog or unless she has longstanding STRONG feelings about it and has been made clearly aware of the down-sides, I'd vote for keeping her where she is. Yeah, school is sometimes boring, it does not necessarily have much to do with the challenge of the academics or lack thereof
You're a smart cookie, you can make sure she is academically challenged in activities at home (which is where an awful large portion of learning does, or anyhow should, occur *anyhow), it is very unlikely to hurt her to stay with her peers and her chances for good social integration are better.
JMO of course, good luck with a difficult decision,
Pat, bored through most of K-12 despite 'gifted' classes but boy if I'd been put ahead grades it would have been a *bad* mistake... and
despite hating school and being bored by it, I still ended up with a PhD and a research/teaching career, so, goes to show, it is not necessarily the end of the world