So I finally installed Visual Studio 2008 (Orcas) Beta 2 on my work machine. Let's see from the perspective of a busy developer what's new and what's cool. And what is not.
There are some sweet additions to C# language in C# 3.0 you can start using right away. Those are specially auto-implemented properties, object and collection initializers which will simplify your code.
I'll not bother about rewriting about new features C# 3.0, since much smarter people than me already did, so just check, for example, excellent articles by ScottGu:
Bottom line is - C# has few new features, most of them are there because of LINQ (see below). Other are quite simple, so you'll pick them up in 10 minutes flat.
Or you could check cool stuff others are doing with new syntax.
Probably single most important addition to VS2008/C# 3.0/.NET Framework 3.5 is Language Integrated Query - LINQ. LINQ is a general addition to the language, but you'll probably be most interested in LINQ to SQL which let's you use LINQ to query database server without directly writing SQL code.
I recommend reading most excellent tutorials from ScottGu to get up to speed on LINQ to SQL when you are ready to dive in and not sooner:
All in all I think LINQ to SQL is a sweet O/R mapper. No doubt there are better performing mappers out there, but LINQ to SQL will be on every developers machine and will be a first step in O/R mapping for many.
It's fun and not too hard to start with, so I recommend you use it your next mini/pet/internal project.
I don't work much with ASP.NET these days, but I did take a look anyway.
It seems to be a decent step forward, but no ground braking changes as in ASP.NET to ASP.NET 2.0 transition.
There is new design time experience with a split view like in Dreamweaver and automatic CSS editing mode which I didn't like at first, but maybe I did something wrong.
ASP.NET AJAX and Web Projects are now built in, there is a new LiveView control, LinqDataSource is a bridge to LINQ for ASP.NET DataSources.
There is also new aspnet_merge utility to merge multiple assemblies for production use. This seems like a easy enough trick to squeeze some extra performance from your code.
VS 2005 projects in VS 2008
I recompiled some of our current VS2005 projects and it went pretty smooth.
VS2008 will show you import solution wizard when you try to open VS2005 solution for the first time. Unfortunately, you can't open updated .sln files in Visual Studio 2005 although there are no big changes in format. But since .csproj (and probably .vbproj, I didn't check) files are compatible, you can easily have two .sln files - one for VS2005 and VS2008 and work on the same project in both.
VS2008 has a feature called multi targeting. When you import VS2005 project, VS2008 will still target .NET Framework 2.0, so you don't have to worry about missing dependencies on production machines. When you decide you need new feature from Framework 3.0 and/or 3.5 you can change the setting.
Be sure to have your projects on source control so you can check for changes to the code after import. You'll probably have some things to revert like changes in web service proxies like I did.
I have used ReSharper so much, I really cannot code without it. Unfortunately R# 3.0.2 doesn't support any C# 3.0 features yet, so you'll see lots of errors if you use them, but the code will compile. So R# is useless for testing out new language features and LINQ, but it will work ok if you'll be working in 2.0 style.
I have tested VisualSVN 1.2.4 and it just works.
TestDriven.NET also work from the box.
Visual Studio 2008 and Vista
Visual Studio 2008 work ok in Vista. If you want to do ASP.NET stuff you still have to install IIS6 stuff and run as administrator.
Read more about it at Arian's post Working with IIS under VS 2008 Beta 2 and Vista which covers everything you need to do.
Other stuff you might want to know
VS2008 beta 2 has a go-live licence.
VS2008 is scheduled to launch in February 28th 2008, but MSDN subscribers will probably get it month or two earlier.
You can import all your setting from VS2005 to VS2008 during install (or is it first start, I can't remember). Those include keyboard shortcuts, colors, fonts and other stuff. You must reinstall add-ins.
VS2008 feels much like 2005. If you don't want to, there is no need to use any new stuff. Which is good so we can all transition slowly and learn about new stuff as we go along doing our daily developing.
The step from Visual Studio 2005 to Visual Studio 2008 is smaller / easier / less scary that then one from VS 2003 to VS 2005, so don't be afraid. Download free Visual Studio 2008 Beta 2 from Microsoft page, install it and give it a go! If you don't want to mess with your main developer machine, you can get pre-installed VPC images on the same page.
I use VS2008 for all mini projects, testing and concept proofing now. I enjoy discovering new things that I don't know about and haven't read about. Like enhanced error report with call stack when designer fails to load windows form.