The available space in the status bar now updates on its own every couple of seconds. Before, it was read once when a scan finished, so it could show an old number after you deleted files or emptied the Trash.
Available space now includes purgeable space, the same way Finder counts it. Hover over the readout to see how much of it is purgeable.
Reopening a location you have scanned before uses the saved scan more often instead of starting over, so large disks come back faster.