Wavering on Wall Street

NEW YORK (CNNMoney.com) -- Stocks looked set for another shaky session Friday as investors digested readings on economic growth largely within expectations and reacted to security concerns in London.

At 8:35 a.m. ET, futures turned higher, with a comparison to fair value pointing to a slightly higher open for Wall Street, after a raft of economic readings were released.

The core PCE inflation figure for May was 0.1 percent, in line with the expectations of economists surveyed by Briefing.com. Personal spending rose 0.5 percent, just under the 0.7 percent consensus expected by Briefing economists. And personal income for May rose 0.4 percent, just under the analysts' expectation of 0.6 percent.

Futures had been higher in early morning trading, then dipped after a report that London police had found and disarmed a large car bomb in the city's center.

U.S. stocks bounced around Thursday and finished little changed after the Federal Reserve left interest rates unchanged, as expected.

Investors will have a number of economic readings to sort through Friday, keeping an especially close eye on the inflation reading in the government's personal income and spending report, due at 8:30 a.m. ET.

The report is forecast to show personal income up 0.6 percent in May after a 0.1 percent decline the month before, while spending by consumers is expected to show a 0.7 percent rise following a 0.5 percent gain.

But the key number in the report for investors is the so-called core PCE price deflator, which shows prices paid by consumers, excluding food and energy. The Fed is generally believed to want to see that reading's annual change in the 1 to 2 percent range, and in April it came in right at 2 percent, down from 2.1 percent in March. If it comes in below the 2 percent mark Friday, it could give a lift to both stocks and bonds.

Treasury prices were slightly higher in early trading ahead of the report, taking the yield on the benchmark 10-year note to 5.09 percent from 5.1 percent late Thursday following the Fed meeting.

In global trade, European shares got off to a positive start but turned lower after police in London said they had deactivated a suspected bomb in the center of the city. Markets in Asia mostly advanced. The dollar was lower against the euro but higher versus the yen.

Oil prices rose in early trading on concerns about gas inventories, taking it above $70 a barrel. U.S. light crude gained 69 cents to $70.29 a barrel in electronic trading.

In major corporate news, Apple (Charts, Fortune 500) is set to debut its iPhone in what is arguably the most hyped product launch in U.S. history. The iPhone, which can make calls, play music and browse the Internet, is due to go on sale nationwide at 6 p.m. local time. Shares of Apple were up 0.4 percent in early Frankfurt trading Friday.

Two iPhone rivals reported financial results late Thursday.

Research in Motion (Charts), which makes the popular BlackBerry device, reported a higher first-quarter profit that topped forecasts as it added more subscribers than expected and raised its earnings guidance. It also announced a three-for-one stock split, and its shares gained nearly 17 percent in after-hours trading on the report.

But Palm (Charts) shares fell 2.7 percent in after-hours trading Thursday after it posted lower quarterly profit and weaker-than-expected revenue, even as it reported record sales of its Treo smartphones.

Video rental chain Blockbuster (Charts, Fortune 500) said Thursday it expects to close about 282 stores in 2007 as it warned that softness in its in-store rental business in the second quarter to date would affected profits. The company has been shifting more focus to online rental and video download offerings.