Stock index futures rose on Wednesday, a day after sharp losses sparked by new concerns Europe was failing to tackle its debt crisis.

* European stocks rebounded from a two-year low after Germany's top court rejected a series of lawsuits aimed at blocking the country's participation in bailout packages for Greece and other euro zone countries.

* The court also said the government must seek approval of a parliamentary committee before granting aid, which could further slow a response to the debt crisis.

* Yahoo Inc will be in the spotlight after Chairman Roy Bostock fired Chief Executive Carol Bartz over the phone on Tuesday. Chief Financial Officer Tim Morse took over as interim CEO. Yahoo shares rose 6.9 percent to $13.80 in premarket trade.

* Nvidia Corp gained 5.5 percent to $13.90 premarket after the chipmaker forecast sales well above expectations.

* Bank of America Corp , which has lost almost half of its market value this year, said the heads of consumer banking and global wealth and investment management left in a broad reorganization. The stock rose 2.3 percent to $7.15 premarket.

* S&P 500 futures advanced 13.5 points and were above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures were up 111 points, and Nasdaq 100 futures gained 25.25 points.

* President Barack Obama, facing waning confidence among Americans in his economic stewardship, plans some $300 billion in tax cuts and government spending as part of a job-creating package, according to various reports. Obama will unveil his plan in a speech on Thursday.

* Stocks fell for a third day on Tuesday on fears Europe was failing to tackle its debt crisis, prompting worries the market was heading to new lows for the year.

(Reporting by Angela Moon; editing by Jeffrey Benkoe)