Converting from VB5 to VB6

Hello everyone. I have a quick question. Hopefully it's quick. I am currently working with a developement team that has been tasked to "convert" a 1997 MS Office based application that uses Excel 2003 (VB5 Macros) and Access 97 to a 2010 MS Office application that will use Excel 2010 (VB6) and Access 2010. Some quick questions:

1. Are there major programming differences between VB5 and VB6 ? I am talking specifically about Excel here. I am working with approximately 5,000 lines of code. The project involves susbtantial use of userforms. How much/and what kind of items will have to be reworked?
2. What are the differences in Access 1997 and Access 2010 ?

I am also curious, from the point of visual basic programming, if there are major differences in Excel 2007 and Excel 2010 ?

Thanks?

1. Excel 2003 is VBA6, not VBA5.
2. This isn't an Access forum.

Some examples:

what doesn't work anymore in Excel 2010:
creating commandbars & adding controls to commandbars in VBA
application.filesearch
distributionlists (hasroutingslip)

What didn't exist in VBA (97)
split, filter, join
Wtih .... End With

None of those are really related to VBA, in fact. The ListView control is entirely separate and, to the best of my knowledge, is dependent on the version of Windows you have, not Office.

Some calendar controls, etc are not available in Excel 2010

I trust you are not planning to use 64 bit Office?

None of your activex controls will work (and many of your add-ins will probably break). Even MS does not recommend using it unless you need to work with really big files.