Microsoft Corp. has upgraded its instant-messaging client Messenger, adding video and voice services for subscribers and features geared toward advertisers.

MSN Messenger 7.0 includes PC-to-PC videophone and voice-only services, PC-to-mobile text messaging, available in the spring; and photo-sharing options. But besides the consumer features, Microsoft launched late Wednesday new services that look to integrate advertising deeper within the Messenger experience.

Messenger subscribers will be offered graphics and animation that can be used as an identifier, but are also tied to an advertising campaign, such "Miles Thirst," the animated spokesperson for soft drink Sprite, a brand of the Coca-Cola Co.

In addition, advertisers can host a brief commercial before a subscriber begins a videophone conversation. They can also place text ads at the bottom of the MSN Messenger screen, or integrate their brand in the Messenger screen through "tabs," which are places consumers can click to go directly to information and services related to the advertiser on the MSN network.

Advertising within instant messaging services available at no charge is not new. MSN competitors Yahoo Inc. and America Online Inc. also integrate advertising with their IM services.

Consumers, for the most part, accept advertising as a trade off for not having to buy the software or services, Joe Wilcox, analyst for JupiterResearch, a division of Jupitermedia Corp., said Thursday.

"Consumers say they're annoyed with a lot of different types of advertising, but just because they're annoyed with it doesn't mean they're going to change their behavior (and abandon the service)," Wilcox said.

There is a threshold, however, that advertisers shouldn't cross, if they want to build a positive relationship with potential customers.

"A lot depends on the annoyance factor," Wilcox said. "I see a difference between an ad that's there and you can see it, and something that makes you stop and wait before you can move on."

Nevertheless, it's clear that Microsoft and advertisers will continue to push the envelope in reaching consumers through Messenger or other MSN services. Messenger alone has 155 million subscribers worldwide who send more than 2.5 billion instant messages a day, according to Microsoft.

"Integrating great advertising opportunities is core to our product development process," Joanne Bradford, vice president and chief media revenue officer for MSN, said in a statement released Thursday.

Besides launching the Messenger upgrade, Microsoft moved its MSN Spaces out of beta, and announced advertising opportunities within the web log, or blog, service, which lets subscribers post personal journals, photos, music lists and other content. Spaces, which was introduced in late 2004, has more than 4.5 million blogs, according to Microsoft.

Volvo Cars of North America LLC, for example, has bought an ad package that includes an ad on the Spaces homepage, text links with graphics at the top of users' personal blogs, and its own sponsored blog.

In integrating advertising in Messenger and Spaces, Microsoft is trying to piggyback on the relationships people build on the services with family and friends to spread an advertiser's message.

"The community or relationship pull would be strong (for advertisers)," Wilcox said.

Other features in Messenger 7.0 include a "shared-search" button that people can use to look up topics or products while chatting. The service's PC-to-mobile service would enable people to send, and receive, messages to mobile phones, even if the cellular phone users don't have an MSN Messenger account.