It's tempting for CMS vendors to develop or resell portals, too, since many of their customers lack a robust content delivery environment. Vignette and Interwoven have done so, and now Percussion has jumped into the race -- helpfully noting that its offering is directed more at workgroups than enterprise integration. Think of it as MS Sharepoint running on Java. Percussion's portal offers several nice widgets for workgroups, but we should point out the significant difference between managing collaborative projects vs. the collaborative development of web content. For the former, a collaboration portal is useful, but for the latter, you really want to focus on the native collaborative workflow capabilities of your CMS (and most of them aren't very good at it)...
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