So, what are people's thoughts on investing in municipal bonds through an ETF such as INY?

I suppose they are easier to invest in that owning particular issuances, and hopefully, because it invests in an index, there is not a lot of turnover to worry about -- but what is the average yield, etc., and are there better ways to earn a tax free yield with less risk of market volatility?

I hear a lot about people investing in municipal auction rate securities, but can't really wrap my mind around whether I am comfortable going that route myself.