A couple of points ... Bear in mind though I'm not in the Product Management group, just the (poor, old :)) Engineering side of things :
* As JW2 said we only had access to the regular Beta, at first though we have had a few builds released to our development team which addressed specific bugs/issues that we have encountered.
* It is a *huge* rewrite exercise. The interfaces that our Addin uses are no longer available. The interfaces have been in development by Microsoft for years, so simply not have them available to us, is a challenge. Add to that, during the beta there was little to no documentation on how we could hook into the new Object Model. There still isn't "much", when you compare it with the "old" interfaces.
* As JW2 said it's not just development effort it's also a huge QA effort.
* We have an additional version of Exchange to test against, and, an additional 'format' (since Outlook 2010 is available in 64 bit flavours too).
In addition, as you're going for Windows 7.. why not use XP Mode to have your Office 2007 installation? You're not violating any licensing agreement there, I wouldn't think -- though you'd have to check to be certain (I can't advise you on the in's and out's of Microsoft licensing). I certainly run Outlook 2007 in Windows 7 XP Mode, and it's great.
Hope that heps shed a little bit of insight in "why it takes so long" .. rest assured you are not the only one who wishes it were quicker.
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