VS 2012: Scroll Solution Explorer to current file

If you need one-off sync with the solution pane, then there is new command "Sync with Active Document" (default shortcut: Ctrl+[, S). Explained here: Visual Studio 2012 New Features: Solution Explorer

Yes, you can find that under

Tools - > Options - > Projects and Solutions - > Track Active Item in Solution Explorer

It's off by default (as you've noticed), but once it's on, Solution Explorer will expand folders and highlight the current document as you switch between files.