There has been a gap between C# and VB for awhile now. VB generates a lot of code for you. For example, hitting enter after finishing an "If" statement will automatically add the "Then" at the end of that line if you left it off, and close it off with the "End If" portion. In C# it's up to you to add those starting and closing {} curly braces.
VB has had background compilation long before C#. In fact, that was one of the major appealing factors of using ReSharper, which provided such functionality. However, as of VS 2008 / .NET 3.5 SP1 that all changed. You can read Scott Gu's post about that here, but I'll paste the relevant part:
"The C# code editor now identifies and
displays red squiggle errors for many
semantic code issues that previously
required an explicit compilation to
identify. For example, if you try to
declare and use an unknown type in the
C# code-editor today you won't see a
compile error until you do a build.
Now with SP1 you'll see live red
squiggle errors immediately (no
explicit compile required)."
Using CodeRush or ReSharper definitely enhances the experience with the autocompletion of common statements which would make a VB developer feel like there has been a seamless transition.
That doesn't quite address technical concerns, but the development teams are different and didn't necessarily do the same thing. In other words, there's not likely to be a shared approach. This blog post excerpt, by a Technical Lead on the VB team, supports this:
“Background compilation” is the
feature in VB that gives you a
complete set of errors as you type.
People who move back and forth between
VB and C# notice this, but VB-only
developers may not realize that other
languages such as C# don’t always give
you 100% accurate Intellisense and
don’t always give you all of the
errors that exist in your code. This
is because their Intellisense engines
are separate, scaled-down compilers
that don’t do full compilation in the
background. VB, on the other hand,
compiles your entire project from
start to finish as Visual Studio sits
idle, allowing us to immediately
populate the task list with completely
accurate errors and allowing us to
give you completely accurate
Intellisense.
One final note is the recent Channel9 interview with the Group PM of the C#/VB/F# team, Luca Bolognese, where he emphasized how the languages are no longer going to stray off in different directions and will begin to share their similarities. So it looks like the future holds great things!
