We just updated the test server. Here's a quick list of things to look for. We'll get a full change-list out to you soon.

Respawn selection: Pick a grid square and respawn at a random location within that square
Vehicle Anti Hoarding measures are in place: First pass
Nomad Server: No base building. NOTE: Zombie pop adjustments for Nomad are not on test yet.
Bullet conversion has been removed
Loot should be more scarce
There are now map indicators for yourself and your group.

Expect a few more test updates in the coming days.

EDIT: The server labeled "Experimental" is NOMAD ruleset
Source: Reddit