Harmonicdoc has released MultiTrack 1.1 (App Store link), a $14.99 application that turns your iPhone into a 16-track digital audio recorder.
Features:

Stereo Recording – up to 16 stereo or mono tracks
Fader, pan, mute and solo for each track
Metronome – never miss that beat again
Time Signatures – various musical time signatures
Ruler – shows where you are in [...]

Blue Microphones has introduced Blue FiRe, a free, high-fidelity field recording app for the iPhone and iPod Touch.

Blue FiRe is optimized for use with Blue Microphone’s Mikey microphone, which attaches to the iPhone and iPod touch.

Olympus has announced a new portable audio recorder, the LS-11, a follow-up to their LS-10 handheld audio recorder.
The LS-11 can record 24-bit/96kHz stereo WAVs, as well as MP3 and WMA format files.
It’s got the same on-board microphones as the LS-10, as well as rear-mounted speakers for auditioning recorded material.
New features include 8GB of internal memory, [...]

Sony has introduced a new portable audio recorder, the PCM-M10 Linear PCM Recorder.
The PCM-M10 is designed to be small and rugged, but offer an extensive range of features, including:

dedicated transport buttons;
a five-second pre-record buffer;
WAV and MP3 format record and play;
USB port for easy upload/downloads;
Digital Pitch Control;
a MicroSD/Memory Stick Micro slot;
96 kHz 24-bit recording; and
4 GB [...]

Calabarock (App Store link) is a free internet-enabled multi-track audio recorder for the iPhone.
When you create a track in Calabarock, it’s available almost instantly in MP3 format on calabarock.com for others to hear.
The new track is also available instantly for other musicians to play on top of, just as if you were in the studio [...]

Alesis product Specialist Rob Bachi gives a quick overview of the Alesis MultiPort iPod Mixer – a device that lets you use your iPod as a fairly sophisticated audio recorder.

Podcasting gear update:
Tascam’s Johnny DeLeon gives an overview of the TASCAM DP-004 Digital Pocketstudio at the 2009 NAMM Show.
TASCAM’s DP-004 Digital Pocketstudio is a portable digital audio recorder that can record two sources at once to the included 1GB SD Card. It retails for about $200.
Details below.

Griffin has introduced iTalk Premium (App Store link), which is basically an ad-free version of its iTalk iPhone recording app. 
Griffin iTalk lets you record on the iPhone or 2G iPod touch. Your recordings are saved for replay on your iPhone or iPod, and you can use iTalk Sync (a free download) to drag-and-drop them as AIFF [...]

Earlier in the year, we had a preview of Belkin’s GoStudio iPod Recorder.
Belkin has now released full information on the GoStudio, and it looks like it will be a hot, reasonably priced device for recording directly to your iPod.
Here are the details:

Record directly to your iPod in 16-bit, 44kHz digital audio quality
Instantly play back your [...]

The Belkin GoStudio is a portable podcasting studio designed to let you capture high-quality audio recordings on-the-go and then publish directly to iTunes when docked.
Features:

Dock lets you record directly to your iPod
Built-in microphone
Built-in speaker for playback
Inputs: Dual XLR,  1/4 in
Battery powered
Recording meter
Gain control and a compressor/limiter

The Belkin GoStudio is expected to be available this summer.