Wednesday's ETF Winners & Losers

Bundled securities tracking utilities were among the best performers of Wednesday's wild session.

Among individual names, Exelon (EXC Quote), American Electric Power (AEP Quote), Edison International (EIX Quote) and FirstEnergy (FE Quote) were all rising by 2.6% or more.

The Ultra Utilities ProShares (UPW Quote) was adding $1.74, or 2.4%, to $74.73. The PowerShares FTSE RAFI Utilities (PRFU Quote) gained $1.24, or 2.3%, to $56.30. The Utility HOLDRs (UTH Quote) was higher by $2.22, or 1.6%, to $138.73. The PowerShares Dynamic Utilities (PUI Quote) was up 29 cents, or 1.6%, to $18.57.

The United States Natural Gas (UNG Quote) ETF was also climbing, as natural gas was gaining 21 cents to $6.40 per million British thermal units. The ETF added $1.33, or 3.4%, to $40.69.

A ramp up in shares of Merck (MRK Quote) boosted several pharmaceutical ETFs. On Tuesday, a New Jersey court ruled that English and Welsh patients cannot sue the company over health problems emanating from the use of the painkiller Vioxx. Shares of Merck were up 2.3%.

The SPDR S&P Pharmaceuticals (XPH Quote) rose 31 cents, or 0.9%, to $33.30. The Pharmaceutical HOLDRs (PPH Quote) was gaining 81 cents, or 1.1%, to $77.70. The iShares Dow Jones U.S. Pharmaceuticals (IHE Quote) was up 5 cents, or 0.1%, to $52.54.

On the other hand, ETFs tracking REITs and the housing sector were lower on fears of spreading credit problems. First, Bear Stearns (BSC Quote) said that it is facing losses in a third mortgage-related fund. Additionally, rumors abounded that Beazer Homes (BZH Quote) had a liquidity problem that could lead to a bankruptcy filing. The company later denied the rumor, but not before it took down the rest of the homebuilder stocks.

The iShares FTSE NAREIT Retail (RTL Quote) was losing $2.50, or 6.2%, to $38.18. The iShares FTSE NAREIT Mortgage REITs (REM Quote) was lower by $2.35, or 6.7%, to $32.50. The Ultra Real Estate ProShares (URE Quote) slumped $1.19, or 2.9%, to $40.06.

Elsewhere, the iShares Dow Jones U.S. Home Construction (ITB Quote) was losing 96 cents, or 3.6%, to $25.60. The SPDR S&P Homebuilders (XHB Quote) was down 59 cents, or 2.2%, to $25.87.