I've asked Yamaha US to give me some more details about the Tyros sequencer and here's what I received today:

"At this time, there is no sequencing program bundled with Tyros. However, the recording and editing on Tyros is easy and intuitive.

For example, to record a song we offer a Quick Record mode (great for when you come up with an original song idea), Multi Record mode, where you can create your recording track by track and we also offer Step Record mode where you can input both note and chord data manually. Tyros also allows you to record the setup on the keyboard (MIC setting, how you have the Score or Lyrics screen setup, panel settings including what voices you have chosen for R1, R2, R3 and L1 etc.) and save that with the song. Very handy for professionals. And, as mentioned in an earlier e-mail, Tyros has an incredible timing resolution of 1920 ppq.

Once you have made the recording, you can punch in and out, start re-recording from a point in which you touch the keyboard or just re-record the whole track.

After you have your song basically the way you want it, you can perform the following edits:

Quantize: You can perform the normal quantize functions plus Tyros allows you to quantize in two different values at the same time. For example, you could quantize both straight eight and triplet eight figures simultaneously. You can also set the strength (1-100) of the quantize (this function is found in sophisticated computer music software) to maintain the human feel. In other words, if you tell it to, the keyboard won't line up every single note on the beat, but will simply tighten up the performance a bit, moving notes closer to the beats.

Change the octave up or down up to 2 octaves of any channel.

Editing in the Step Record mode allows you to go in and change the values of individual notes, program changes, pitch bend values and control changes (panning, volume, reverb etc.) etc. You can also cut, copy and paste SysEx data. It should be noted that you can select sections of data and perform changes to multiple sections at once."