What's New in the BCL in .NET 4 Beta 2

 

What's New in the BCL in .NET 4 Beta 2 [Justin Van Patten]

Visual Studio 2010 and .NET Framework 4 Beta 2 are now available to download.  .NET 4 Beta 2 contains several new BCL features and enhancements in addition to what was included in .NET 4 Beta 1.  Many of these improvements were added in large part due to specific feedback and suggestions reported by customers through Microsoft Connect.

Summary of New BCL Functionality in .NET 4 Beta 2

• Complex Number
• Location
• IObservable<T>
• Stream.CopyTo
• Guid.TryParse, Version.TryParse, and Enum.TryParse<T>
• Enum.HasFlag
• String.Concat and String.Join overloads that take IEnumerable<T>
• String.IsNullOrWhiteSpace
• Environment.SpecialFolder additions
• Environment.Is64BitProcess and Environment.Is64BitOperatingSystem
• Path.Combine params support
• TimeSpan Globalized Formatting and Parsing
• Stopwatch.Restart
• StringBuilder.Clear
• IntPtr and UIntPtr Addition and Subtraction operators
• ServiceInstaller.DelayedAutoStart
• ObservableCollection<T> moved to System.dll

http://blogs.msdn.com/bclteam/archive/2009/10/21/what-s-new-in-the-bcl-in-net-4-beta-2-justin-van-patten.aspx