ASP.net 3.0 is the latest version. Released November 6, 2006 it positioned ASP.net for the Vista operating system. It is generally regarded by the technical community as a marketing update.

ASP.Net 2.0 was a major technical upgrade. It was released November 7, 2005 as a generational upgrade to the 1.1 framework. Applications written to run under 1.1 will run under 2.0 with minimal modification but this was a big upgrade with lots of new features and direction. ASP.Net 2.0 is designed to make programming easier and to improve performance. There are hundreds of improvements, new controls, more client side interaction, etc.

If you weren't all that familiar with 1.1 you might not even notice the difference...if you were very familiar you'll notice lots of details have changed....like KeyDataField used in a DataGrid becomes KeyName in a GridView. Its a good thing that the development tools contain Intellisense so we don't have to remember all this stuff but it is irritating.

Partial classes make it easier to use code behind as you no longer have to declare all the controls from your HTML in the code behind page. I haven't run into any problems with partial classes other than the need to use the CodeFile and Partial Class keywords.

Master pages will be a useful feature. They let you design a consistent layout for your site, capture that layout in a single HTML/CSS page and then reference that "template" from what ASP.Net 2.0 calls content pages. Unfortunately in 2.0 there are some gotcha's particularly if you are using old style controls and javascript rather than ASP.Net server controls. I am particularly having a problem when the form is defined on the master page and an old style html input tag is used in the content.

A few of the new ADO data source features look promising but contain problems for sophisticated programmers. The new datasource controls offer rapid application development.They tremendously simplify the process of databinding to the new DataView control. It takes some effort to find out how to use them with parameter driven stored procedures, but it still works and it is easier than ever.

The forms authentication security model was pretty good for implementing forms based login security and the new login forms provides a good role based implementation encompassing many best practices. Since I've already implemented the authentication ticket model and store my users and roles in a SQL Server database I am not sure how I would use the new login forms. One feature I find missing from 2.0 is the ability to assign an unauthenticated returning user some limited privileges if he returns a Consencis cookie that matches an entry in my database.

The Navigation pages initially looked ugly and useless to me until I started looking into a custom sitemap provider. Consencis sites are all data based structures rather than file based or static so the default XML provider looked awkward. The process still looks awkward but may have some promise so I'll return to it later. For now all Consencis sites use Navigation controls including the menu, breadcrumb trail,  topic tree, search, sequential controls and footer menu. All are data based, consistent with the security systems and fast!

Controls updates and new controls like the tree control are always good. Improvements to the validation controls may finally make them more useful. the new Grid controls GridView and DetailsView are substantial improvements over the DataGrid. Grid View plus Data Sources works to allow programmers to very quickly prepare some very capable pages.

The new client side features are fascinating. OnClientClick and MaintainScrollPosition are pretty basic but the Client-Side Callback opens all sorts of (Ajax like) possibilities. Microsoft seems to be calling this Atlas. More on this later.