What file systems does Apple use in iPhones? HFS

WWDC 2012 Session 709, ￼What’s New in the File System, presented by Deric Horn included the following observation: Journaled HFS+ everywhere.

In the iOS Developer Library, NSDictionary Class Reference contains references to HFS. 

Do iPhones use HFS Plus?

Journaled or not journaled?

I'd like an authoritative reference. Thanks. 



Types of HFS Plus

iOS and iPhone aside for a moment … Apple's hdiutil(1) Mac OS X Manual Page lists four HFS filesystem types for creation purposes:


HFS+
HFS+J (JHFS+)
HFSX
JHFS+X




Postscript

Beyond the accepted answer … as Apple sometimes distinguishes between JHFS+X (journaled, case sensitive) and HFSX, so: 


extra kudos to anyone who can verify whether, in an iPhone, both HFSX slices are journaled 


… I do have fileXray, but I don't foresee myself making an ssh connection to my first generation iPhone ;-)
According to iOS Forensic Analysis, the main filesystem is HFSX.

HSFX
All Apple mobile devices use HFSX as the file system. HFSX is a variation of HFS+ with one major difference. HFSX is case sensitive.

HFSX is reported by Apple as Mac OS Extended (Journaled, Case-Sensitive).
There are two main partitions of HFSX: the OS and the user data. Prior to these partitions is the usual MBR partition (around 100 MB).

SSHing into my jailbroken iOS 6 device seems to support this, since I can create case-sensitive directories. Creating the following directories was no problem:
$ mkdir test
$ mkdir Test
$ mkdir TEST