Wall Street’s financial meltdown promises to forever change the way information technology spending is handled in the securities industry as the old giants of the capital markets stumble and banking behemoths move in to devour them whole or in part, scooping up technology assets.

Lehman Brothers last week tumbled into bankruptcy, sparking London-based bank Barclays to pounce at choicest morsels that include two Lehman’s data centers and its New York City headquarters building, at a fire-sale price. At the same time, Merrill Lynch & Co., facing its own troubles, agreed to be acquired by Bank of America for about $50 billion in a stock-swap deal. These stunning developments signal a new era in which more often banks will be in control of IT spending for securities trading technology, and analysts foresee a culture clash coming.

See just how much Wall Street's fat cats earned before the industry meltdown.

“Banking tends to not need real-time information as much as capital markets,” points out Sean O’Dowd, senior analyst at Financial Insights, an IDG Company. “Banks do batch overnight. Capital markets do millions of transactions processed in milliseconds. It’s a different type of culture.”

“It’s the cornerstone of what the next generation of this industry is going to look like,” says Robert Iati, partner at TABB Group, a research firm that closely watches the North American securities industry.

And changes may be in store for Wall Street’s last two standing investment houses, Morgan Stanley and Goldman Sachs, which are fighting the most severe market meltdown since the 1930’s because of the credit crunch.

In this new era, banks buttressed by their core lending will be taking the lead as “one-stop shops,” says Iati, with Bank of America possibly becoming a global powerhouse like Citibank, UBS or JPMorgan.

But what are the implications for jobs and spending on IT assets in the securities industry accustomed to lavishing fabulous sums on ultra-fast networks to compete in electronic trading, where today even a nanosecond may count?

Click to see: Bar chart showing securities industry spending on IT assets and staff

“Merrill last year spent between $3.5 and $4 billion on people and technology,” says Iati. “Lehman’s outlay was $2.5 to $3 billion.” But TABB Group, largely as a result of last week’s events, predicts a sharp decline in IT-related spending for the North American securities industry, from $24.2 billion last year to $21.9 billion this year and down to $17.6 billion next year.