A recent article by Pensions & Investments discussed the status of ETF regulations in the U.S. and Europe. The SEC has previously announced that it is conducting a broad review of ETFs that will look at the adequacy of investor disclosure, liquidity levels and transparency of underlying instruments in which ETFs invest, fair valuations, efficiency in the arbitrage process and the relationship between market volatility and ETFs. According to the article, several sources said that this review is so broad it's unlikely to result in new regulations in the near future.
In Europe, the European Securities and Markets Authority recently proposed regulations that would require ETFs to disclose whether they lend securities and provide information about the collateral they hold. Final regulations are expected by mid-2012. The agency has also talked about creating a classification system for ETFs and even prohibiting the sale of more complex ETFs.