* Bank of America falls in premarket after results
* Best Buy down in premarket after holiday sales
* Initial claims data due
* Futures off: Dow 8 pts, S&P up 3.25 pts, Nasdaq off 9.75 pts (Adds Citibank earnings, Swiss ADR moves)
By Chuck Mikolajczak
NEW YORK, Jan 15 (Reuters) - U.S. stock index futures dipped in choppy trading on Thursday, fluctuating between gains and losses, after the Swiss National Bank scrapped its three-year euro cap on the franc.
* Trading was volatile, and futures erased early gains after the SNB said it would discontinue the cap it introduced on Sept. 6, 2011 to fight recession and deflation threats.
* Swiss stocks traded in the U.S. moved higher in premarket trading, including UBS, up 7 percent at $17.45, Credit Suisse, up 3.9 percent at $23.70 and Novartis, up 7 percent to $103.63.
* Bank of America lost 2.7 percent to $15.60 before the opening bell after the second-largest U.S. bank by assets reported a 14 percent slump in quarterly profit.
* Citigroup shares fell 1.1 percent to $48.49 before the opening bell after posting quarterly results.
* Dow component Intel Corp is scheduled to report after the closing bell.
* Expectations for U.S. fourth-quarter earnings have fallen sharply in recent months, with growth now estimated at just 3.6 percent compared with an Oct. 1 estimate for 11.2 percent, according to Thomson Reuters data.
* U.S. stocks dropped for a fourth day Wednesday in volatile trading after a World Bank forecast added to worries about the health of the global economy.
* The benchmark S&P has fallen in nine of the past 11 days. The index is down more than 3.8 percent from its last record high Dec. 29.
* Economic data due Thursday include weekly initial jobless claims, Empire State Manufacturing for January and the December producer price index for final demand at 8:30 a.m. (1330 GMT). The Philadelphia Federal Reserve Bank's reading on factory activity is due at 10:00 a.m. (1500 GMT).
* Best Buy shares tumbled 7.3 percent to $37 before the opening bell after the electronics retailer posted holiday sales results and said it expects same-store sales growth to be flat to negative in the first two quarters of its fiscal year .
* U.S.-listed shares of Blackberry dropped 14.7 percent to $10.74 after South Korea's Samsung Electronics said it had no plan to buy the smartphone maker, denying a Reuters report on a takeover approach.
Futures snapshot at 8:09 a.m. (1309 GMT):
* S&P 500 e-minis were down 3.25 points, or 0.16 percent, with 366,066 contracts changing hands.
* Nasdaq 100 e-minis were down 9.75 points, or 0.24 percent, in volume of 68,256 contracts.
* Dow e-minis were down 8 points, or 0.05 percent, with 82,600 contracts changing hands. (Editing by Bernadette Baum)