Shares of large Internet companies together with Yahoo Inc. felt under pressure amid concerns about its advertising exposure to the softening real-estate market.

An RBC Capital Markets research report on the topic seemed to dampen on any upside gain Yahoo had hoped to achieve from announcing its social-networking feature, called del.icio.us, has tripled its audience size to more than 1 million during the past nine months.

Also hanging over Tuesday's trading were a bevy of new reports about 2006 online ad spending from the day before. While some, like eMarketer Inc.'s, revised annual projections downward, the three reports are generally upbeat and expecting another record year.

The Dow Jones Internet Index will post less-than-stellar third-quarter financials. William Blair & Co. estimated the number of eBay sales listings during the quarter, a key measure of its health, is on pace to grow by about 30% from the year ago period, which is 2 percentage points less than most analysts expected. Shares of eBay were up about 3.5%.
Google Inc. shares were trading up, fractionally, after announcing its controversial book search project will now include millions of books from Complutense University in Madrid, marking the first non-English speaking collection to be scanned.

Among other stocks, online advertising and marketing firm 24/7 Real Media Inc. shed 2.4% early following a warning from analysts at Jefferies & Co. to expect volatility in the shares because its convertible debt was maturing Tuesday.

Edwina Baniqued