First, Outlook will replace Entourage which is the e-mail and groupware application that is included in the current suite. Eric Wilfrid of Microsoft that this decision was made because it will give business users of the Mac version of the suite more of the same features Microsoft already offers for people using Office on Windows.
Also, instead of three editions, there will just be two. The Mac Business Edition will be released next month.
Source: PCWorld

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Lee

Is Microsoft pre-announcing this so far in advance to discourage Entourage users from switching to the new Exchange-compatible versions of Apple Mail and iCal in Snow Leopard (10.6)?
Just use Open Office which is free and has the ability to open and save in more file types than MS Office ever has, can, or will.
Yes, Open Office is great replacement for Documents, but it doesn’t have the part which replaces Email and Organizer client, like MS Outlook/Entourage is.
“Yes, Open Office is great replacement for Documents, but it doesn’t have the part which replaces Email and Organizer client, like MS Outlook/Entourage is.”
For that, you use Kontact on the client PCs and Citadel on the Server PC. If you need Crackberry support, well, then yer stuck with M$ Exchange.