The configuration drop down list is located in the standard toolbar. But you
will not see a "Release" mode for web applications anymore. This is now
controlled by the web.config file.
From the Tools menu, choose Customize. Click the Commands tab, select the
Build category, and then from the commands list drag the Solution
Configurations command to the toolbar
From the Tools menu, choose Customize. Click the Commands tab, select the
Build category, and then from the commands list drag the Solution
Configurations command to the toolbar