I'm a Pro Tools user, and a long-time Machead.
I can't say that this "iTraks" (I actually like the name "iMix" better) will actually see the light of day as a standalone iApp, but could see some basic stereo record/edit features showing up in iTunes 4. This way, Apple's not introducing another audio portion of the iLife tree, but you still get these nice audio features that would intigrate smoothly with iMovie, Final Cut Express, and even FCP. I imagine iTunes 4 will compress audio to .mp3, .aac, .ogg, .shn, etc. This could segwey to a recordable iPod, using iTunes 4 record features to capture uncompressed .aif files. Dump those uncompressed .aif files into your Mac, edit in iTunes 4, compress to whatever standard you like, and burn a disc or rip files to your new iPod. Neat-o.
I have also bee expecting/hoping for a multitrack recording/editing app, much in the vein of a Pro Tools (IMHO, the best DAW alive), snuggling up nicely with FCP... maybe called Mix Master Pro (MMP). Thi sapp could handle multi track audio and MIDI, having all the expected features of a $999 app.
Again, while I am a PT user, you just can't' match Apple's intuitive design (hard or software). And I support and would be interested in an Apple branded multitrack app.
And with recent announcements of FCE, I could also see an "lite" version of MMP, something in the $299 range. Mix Master Express (MME)?
With all that said (written), Pro Tools offers a free, stereo record/edit app, Pro Tools Free. This is an excellent marketing tool, as it gives one access to the Pro Tools environment - for free. Thus growing and solidifying it's market base. So maybe an iTraks will show up. What do I know?
Stay tuned.