Boot Camp OS startup selection not available with Windows Alt
Actually, Boot Camp installs a Boot Camp Control Panel in the Windows Control Panel. The large icon appears as shown below. 



Also, Boot Camp installs a gray diamond icon in the Windows notification area (system tray). 



By clicking on this icon,



a menu will appear,



which allows you to easily switch back to OS X.

Upon opening the Boot Camp Control Panel, the Windows icon will be highlighted.



If the OS X icon is selected followed by clicking Apply or OK, the default startup partition will change back to OS X without the system restarting.   



The same is true for the Startup Disk window under System Preferences for OS X.

In conclusion, the only functionality missing is a menu to select an operating system on start up. I suppose rEFInd would serve this purpose. I will point out there are others for which you have to pay for. For example, there is Boot Runner which has a 14 day trial period. It installs in the OS X partition and can be uninstalled. rEFInd may have problems with both installs and uninstalls.