a VBA solution will be supported by MSOffice for many years to come: even
XLM is still supported in Excel 2007 and that was obsoleted by VBA many
years ago (1993) in Excel 5 .

I dont see the point in trying to develop an Excel addin for .net and VSTO
until they are properly supported and functional under Office: I believe
VSTO is currently targeted at a different marketplace.

Proper .net/VSTA support may or may not happen in the next office version
(14) but I have not heard any public Msoft announcements to that effect: it
would require a major development effort by MSoft that might not be
cost-effective for them.

On the other hand I believe there is a public statement that VBA will be
supported in the next Office version.

If you want a solution that supports Excel 97 through Excel version 14 I
personally dont see much choice at the moment other than VBA or VB6 or a C++
XLL.
If your marketplace is large corporates then you can probably drop Excel 97,
but I don't think that would make much difference.

Good solutions all, but this is not the best moving forward. You'll
eventually have to embrace .NET and VSTO/Interop...it's just
inevitable. If MSFT was still supporting VB6 and COM (like they EASILY
COULD HAVE), the above would be the best option.

Charles
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