In the first of two new ads, Apple's PC guy, outfitted with an accountant's green eye shade, sits at a table dividing his cash between an "advertising" pile and a "fix Vista" pile. Of course, the "advertising" pile gets the lion's share, in reference to Microsoft's $300 million Windows campaign.

"Do you really think that amount of money is going to help fix Vista?" Mac guy asks, pointing to the small pile of cash.

"I guess you're right," PC says. "I'll just put it all on advertising."

This taps into a theme I heard repeatedly from people after the Microsoft Windows campaign began airing earlier this fall: I don't care about the advertising. Just make my computer work better.

The thing is, Microsoft has largely done that. The performance of a Vista PC today is worlds better than it was when the operating system debuted 22 months ago. Device drivers and application compatibility, two of the biggest early Vista headaches, have been addressed. But the popular perception remains -- due in no small part to Apple's ads.

Another new Mac ad makes light of the fact that Microsoft's campaign is centered on Windows, not Windows Vista. PC guy holds a buzzer and bleeps out the "V Word."

"We don't say the V Word anymore. It doesn't sit well with frustrated PC users," PC guy says. "From now on we're going to use a word with a lot less baggage: Windows."

This may not resonate as much with consumers, but it does strike at the heart of a marketing challenge Microsoft faces in the next year as it readies Windows 7, Vista's successor. How much noise can Microsoft make around the new OS without inadvertently convincing PC buyers to skip Vista and wait for 7, due out in 2010?

The "I'm a PC" campaign attempted to thread the needle on that issue by going with the broader brand Windows, rather than Windows Vista. But that was also because the campaign extends across Windows Mobile and Windows Live, not just the desktop operating system.

Harry McCracken writing at Technologizer wonders whether the new Mac ads "venture too far into the realm of insider baseball:

"The first one appears to assume that you care about Micorosft advertising budgets, and the second one doesn't make much sense at all unless you've noticed the downplaying of Vista in recent Microsoft ads. Both bash Vista without saying anything positive about the Mac, and they bash it for its promotion as much as for the product that's being promoted."

Here is the first ad, "Bean Counter":

And, "V Word":