Split-panel nautilus tweaks/hacks are incredibly popular but up until now the feature remained a 3rd party enablement.
With the upcoming GNOME Shell raising questions as to the purpose Nautilus due to features Nautilus traditionally provided instead being served-up by the Shell.
Many new directions, features and services are being mooted, such as a live meta-data preview pane: -
Of course, as Holger Berndt’s puts it on his blog: -
The UI is not yet final, and there are a few issues still to be
worked out, but I really like the route that it’s going. So, if all
goes well, there won’t be any Nautilus packages for Lucid in my PPA..
Here’s hoping indeed!
If you’re not up for building GNOME from source you can get Holger Berndt’s pacthed Nautilus via his PPA @ https://launchpad.net/~berndth/+archive/ppa
sudo add-apt-repository ppa:berndth/ppa
sudo apt-get update && sudo apt-get dist-upgrade