I would be interested in ANY 76 note Yamaha arranger, especially a more affordable S910 (or similar) type model, but not having 76 keys is not a deal breaker.
Not having heated seats in my car is not a deal breaker either...although sometimes I wish I had it.

The only need imo for 76 keys (or better yet 88) is if you need to regularly play the keyboard as a solo piano in non-arranger mode. I view an arranger keyboard for what it is, an auto-accompaniment style instrument. For this, 61 notes is more than sufficient as allocating 1.5 octaves (C1-F#2) for left hand chords, still leaves 3-1/2 generous octaves, which is only 1/2 octave less than from middle C to the top note on a full 88 note acoustic grand piano. Tyros 4's got conveniently placed transpose buttons directly next the keyboard's lowest key, allowing you to instantly raise/lower the octave so you can play lower bass notes if/when required. Coming from a lifelong acoustic piano background,I feel simply adapting to the octave transpose button method, well worth the gain of the 61 note arranger's much lighter compact portability. For those 'rare' times when a full evening of solo piano repertoire is required, I'll take my lightweight Roland A33 76 note controller, but why have to drag along a larger heavier keyboard otherwise. JMO.

Songbook, a critically needed feature on Tyros, and one of the key reasons I do not buy one.

Graham, acknowledging the Korg 'Songbook' feature superior , , ,
What specific things about the Korg 'songbook' are missing from Yamaha's closest equivalent feature: 'Reg Bank' Files? Thanks.

Transpose Save also Scott. And Yamaha should utilize the whole size of the Tyros 4 display making it overall bigger to view. Lots of wasted perimeter border space unused? And make it TOUCHSCREEN/Or button operational also

Yamaha 'Registration' files already support saving transpose settings and just about every other setting on the keyboard, including calling up lyric/chord text files too.
The big irritation lies with not being able to call up Registration files from within Music Finder, where your entire songtitle listing can be stored.

This leads to my Korg Songbook question: From Songbook, is it possible optionally call up from your entire song repertoire: either alphabetically, by genre, by artist, etc?

The actual 'viewable' Tyros 4 screen area is still substantially larger, brighter, and more colorfully vivid than the Pa2X/3X and in fact for lyric/text display, @ 16 pt font size: each page supports 64 characters per line and 20 lines per page. Regrettably, the Pa2X/3x's display supports far fewer text characters per line and lines per page. As far as a touch screen goes, until the keyboard manufacturers implement the 'outdoor sunlight viewable' type of touchscreens currently available for the iPad, I'm not interested.

Hi Scott, you can sort your entire song repertoire by Type (mp3, style), Name, Genre, Key, Tempo, Meter. Additionally you can filter your entire songbook by all those criteria plus Artist.