The visual IDE should be the same. The detailed comparison can be found at:
http://msdn2.microsoft.com/en-us/vstudio/products/cc149003.aspx
(just expand + under each category)

Think of standard as all of the Express products in a single IDE with the
enhancements that would make that possible. If that is enough for you,
great.

What Pro will add (that I can run through off hand)
* Better testing tools
* Database projects
* Enterprise type tools like Server Explorer (absolutely necessary for my
work)
* Crystal Reports (not important to me)
* VSTO _ Visual Studio Tools for Office
* Compact Development Tools (Smart Phone, PocketPC, etc.)
* Developer Tests (I would not leave home without them)

For me, I would not want VIsual Studio without the Server Explorer and Unit
Testing, both of which are not present in Standard. The first item is more a
convenience factor and you can do the second (Unit Tests) with nUnit,
mbUnit, etc.

Only you can assess your own needs. The Standard product is aimed more at
hobbyist developers, while the Pro is aimed at Professional developers
(developing is your job).

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