Now since Adobe is also concerned about XPS (PDF Rival) support in Windows Vista, Microsoft will leave it at the hands of PC vendors to decide whether they ship Vista Computers with or without XPS. Clearly, XPS has hit a big stumbling block even before it is realeased to the public and this decision to decouple native XPS support from Windows Vista may drastically hit the XPS adoption rate.
Adobe has generally been keeping mum on the whole episode. They did send an e-mail to The Associated Press explaining their situation
As our CEO Bruce Chizen has stated numerous times in the past, Microsoft has a monopoly and we are always concerned about the possibility that they might abuse that monopoly.That brings one interesting thought in mind - Why is Microsoft so afraid of facing an antitrust suite from Adobe when it has experience of fighting case with US DOJ, EU and Real Networks. The Microsoft thinking looks valid enough. Any lawsuit concerning Windows Vista or Office 12 would mean further delays in the launch which can be more disastrous for Microsoft than not support PDF in Office.
And in this case, Microsoft know that Adobe has a more strong point. Therefore, they are willing to modify and ship stuff based on the terms laid down by Adobe - "We're saying to Adobe, if you have any concerns about Microsoft shipping XPS software in Windows, we will ship anything comparable you want"
More commentary by Joe Wilcox, Ina Fried, Mary Jo Foley, Adobe, Microsoft, pdf