Advertising money may be held back from the television upfronts for use on the network's digital executions, reports MediaWeek.

An estimated $150 million is thought to be withheld from upfront TV commercial buying in favor of online. The good news for networks is that they will still get that money - just in a different envelope.

However, CBS, NBC, ABC, Fox and The CW have plans for their sites, from streaming shows to originally produced content.

CBS is signing a distribution deal that will bring more exposure to its programing via third-party dissemination. NBC and ABC are working on branding their own sites. Fox highlights the multimedia opportunities available for advertisers through MySpace.

It's unclear what payment model each network will adopt for online buys. Some could combine it into a package; others may bill completely separately.

Network sellers are taking their time in closing deals since they do not see potential buyers going elsewhere at present.