VS 2010 - I want my 'Document Map Margin' AKA 'Document Mini-Map'

I’ve just installed VS 2010 Beta 2 and want my “Document Map Margin” feature AKA “Document Mini-Map” like RockScroll. While there are a plethora of recent posts that mention this feature in VS 2010 it isn’t turned on for me, and I don’t see it anywhere in Tools -> Options -> Text Editor where other aspects of the text display are turned on (like the boring standard vertical scroll bar). Nor can I find it anywhere else in Tools -> Options. Or View -> Other Windows or anywhere like that. Normally I’d just read the help, except it wasn’t installed by default. After jumping through a few hoops I was able to install it….but it doesn’t work properly (perhaps that’s why they didn’t install it in the first place). On-line help on MSDN site for VS 2010 doesn’t have anything obvious, but then it’s using BING! for search so I never really got my hopes up. I’ve searched the Online extensions via the Extension Manager (just in case it was an add-on and not part of the base product) but without success. If you can tell me how to turn on this feature I’d be most grateful.