With the lifting of the Securities and Exchange Commission's ban on short-selling, ProShares short financials funds, ProShares Short Financials (AMEX: SEF) and Ultrashort Financials (AMEX: SKF), resumed normal creation activity. 

During the suspension of creations, average daily trading volume of SKF and SEF exceeded 19 million shares, according to ProShares.

There was no word from Rydex this morning as to whether its short financials fund, 2X Inverse S&P Select Sectors Financials (AMEX: RFN), would also be back to normal.

Separately, ProShares announced that it has moved all of its 64 ETFs to the NYSE Alternext platform (the new name for the Amex ETF platform), in response to the completed acquisition by NYSE of the ProFund ETF current trading home, the American Stock Exchange.

The ETFs' closing time will now be 15 minutes earlier, at 4 p.m., in line with the NYSE platform's normal closing time. The new closing time went into effect yesterday. The ETFs are all expected to move to NYSE Arca in the fourth quarter.

While the ban on short-selling has been the biggest problem for these short financials ETFs, more generally, the ETF industry has experienced its first major premium/discount, and bid/ask spread issues, as a result of the abnormal market conditions. 

Many funds have developed wide discounts to net asset value—though most are eaten away by arbitrage players within a few days. What's more, bid/ask spreads have widened, though, again, the general trend before the abnormal market conditions was for bid/ask spreads to be going down across the ETF industry.

Nevertheless, ProShares has felt compelled to add an educational piece to its Web site explaining how ETFs trade, how a premium or discount can develop, and the difference between closing price, intraday indicative value, and net asset value.

The piece also provides investors with tips on how to more efficiently trade ETFs.