What are the benefits to a client of upgrading a system from .Net 2 to .Net 3.5 or 4 [closed]

Question

In a recent interview one of the questions I was asked was

‘What is the benefit to our clients if we upgrade to .Net 3.5/4’.

In other words If we upgrade all of our systems, all our clients will need to upgrade their machines, if we can’t give them valid benefits for doing so they aren’t going to be very happy.

As far as I know while .Net 4 has some overhead with the new CLR and can cause issues.Net 3.5 is more about extra features added to the dot net 2 core so shouldn’t affect anything adversely. I could see various benefits from a developers point of view:

• Linq
• List item
• Lambda expressions
• WPF
• WCF
• Anonymous methods & types
• Extension methods

From the company’s point of view, there is the benefit of attracting developers and keeping your current staff because they are working with the latest technologies.

Several days later the only answers I have come up with are:

• Support for Windows XP is being phased out and that any proactive company should already be well on the way to upgrading their systems. As Windows 7 comes with .Net 3.5 upgrading shouldn’t be an issue
• Support for the latest features in Sql Server 2008

So I have decided to ask here. What are the benefits to a client of upgrading a system from .Net 2 to .Net 3.5 or 4

Answer 1

Clients don't care what framework they are using. They care on the stability of their product which your company has provided them. As you said, if the client is forced to move to a higher OS, then new framework has to be provided. Again you can run your app on win 7 in compatibility mode. So it still works.

If your adding new features of the framework lets say TPL from Net 4 then ask users to move to net 4 as well.

Answer 2

Since we are talking about client benefits, if the app is in WPF I think the Text improvements in WPF on .NET 4 are probably the most significant direct benefit to a client. See http://blogs.msdn.com/b/text/archive/2009/08/24/wpf-4-0-text-stack-improvements.aspx.

Other areas are more likely to produce indirect benefit. Memory mapped files and the task library could lead to improved performance. Along those same lines I think there is an argument to be made that what benefits developers will eventually benefit the client. If a new part of the .NET 4.0 library makes it easier for me to develop a new feature or reduce the amount of code I maintain that will impact the client experience.

There are also some little things you can pick out of http://msdn.microsoft.com/en-us/library/ms171868.aspx: compression algorithms have been improved; new built-in WPF controls; new Windows 7 shell support. I've focused on 4.0, but I'm sure you could pick some additional minor items from 3.5 too. In my opinion, if you are going to require an upgrade I would go all the way to 4.0.