I spent today at Microsofts Techdays Visual Studio 2010 launch event in London.  Lots of interesting stuff, covered in depth all over the internet (just Google, or bing, if you're a sadist "changes from .NET 3.5 to .NET 4.0").  A tiny thing that caught my attention for it's pure utility to the masses is a new operator in ASP.NET 4.0 that deals with Html Encoding of data implicity.

You'll likely be familiar (especially if you're working with ASP.NET MVC) with the <%= notation for referencing properties in the context of the ASP page.  In ASP.NET 4.0 this has been joined by <%: This addition automagically HtmlEncodes any content between the opening and closing tags to prevent repetitive tag soup of <%=HttpUtility.HtmlEncode(myProperty)%> all over your views, and removes the temptation to push HtmlEncoding into your Controller or Model, two places where encoding really shouldn't be a concern.

Just struck me as a nice little change that'll make everyday life that little bit easier for a majority of web developers. Sure it's not quite the new Xaml designer (which is a work of beauty) or Intellitrace (which looked like a total game changer for retrospective debugging), but you know, it's the little things that count.