How to use Versions.app

Initial setup

Start Versions and click one of the big buttons Repository (if you don't have a local working copy already) or Working Copy (if you do have a working copy already) - fill in the details:
Versions: initial view and setup

Working with the local working copy

When all is set up, Versions will give you a status listing directly in the window. It will also indicate how many commits are in the repository since you last updated (2 in the picture below). You can switch between only seeing the modified (and unknown) files, or all files.
Versions: view of working copy

By turning on the inspector, it is very easy to change common attributes:
Versions: working copy with inspector, file selection
or edit the ignore list:
Versions: working copy with inspector, folder selection

Even with Versions (as compared to SvnX), diffs will open in FileMerge. But Versions do a better job at providing the real working copy file, and with a small script (found in $GTHOME/gt/src/filemerge-tools/ - run make there to install), all files will open with the correct encoding, and merges done using FileMerge will automatically be saved back to the working copy file.

Versions: filemerge displays correctly

Make sure that after you have installed the script (named FileMerge_SaveMergedToSecondFile.sh), you open Versions > Preferences, and select the script in the File Comparison drop-down menu:
Versions: the preferences dialog