Nope, havent messed with D7 at all. Just recently installed 6.16 after waiting about a year for it to smooth out. It is each individual's choice as to whether or not they wish to beta test a product, I just do not have time to do testing as my site takes my full-time attention.
My opinion has not changed about ignoring those who are continually complaining about release dates and so forth. When a final version is released, go for it. Until then, either contribute to it's development as you see more have stated, or just deal with it until it does come out.