JQuery validation in MVC 3

MVC 2 moved to JQuery, but that was not fully functionality oriented or we can say that, it was not totally independent functional unit.

For JQuery validation there were no proper features to support it, it always require Microsoft AJAX support by converting the validation support to run on the popular JQuery validation plugin.

The combination of these

JQuery Validation

UNOBTRUSIVE JavaScript support
(For more information about, please go through this blog)
Unobtrusive JavaScript in MVC 3

Provides several functionalities to MVC, some of these functionalities are as follows

Extremely flexibility

Support from JQuery community

Proper Validation handling

Thus from the above description we come to an useful conclusion that JQuery validation was one of the most useful feature of MVC 3 along with unobtrusive javascript and other.