What feature in live 9 would be a game changer for you

[Shokol8]

as a few said a way to get the workflow faster by not interchanging view when you want to cut and chop your audio file, a way to compare two clips to place well your midi or audio signal, especially for the drum parts,when you drum parts walking over each other, a way to split your midi note rather to everytime lenghten it down and duplicate.
Also another thing will to have or pre-draw wave-like style of automation or a kind of oscillator-knob that would be used as an lfo but just to automate some macro knobs so you could assign an lfo effect to nay parameter you want, that will be such a gain of time and creativity! but overall i love ableton anyway, keep it up ableton team! ;D

[3dot...]

a better arrangement window (completely re-think it)...
including shortcuts/macros/editing tools..
better GUI (in terms of flexibilty)...
the current clutter is almost unbearable
yes... go there..
some "other" sequencers got some nice ideas to borrow from (wink,wink Vegas...Protools...FL studio)
or come up with your own... I don't care..

better racks.. (racks are great but there are some major design flaws in the current implementation.. and once again... major clutter browsing racks)

'spectrum' rethink..
'impulse2' ...
'simpler/sampler2'
'reverb2' ...
'arpeggiator2'...

modulation devices (of the cpu efficient non-m4l type)

feedback loops within fx/racks (bitwig feature)

integrated/supported OSC (even without m4l)

OS multi-touch compatibility...

m4l direct access to midi-ports

better API access and proper documentation for m4l users...

improved cpu handling...and GUI responsiveness for Live/m4l..

I would also like synced online jamming function.. but that's science fiction almost...

they got their jobs cut out...
I would settle for proper delay compensation... rock solid clock...
and generally a proper reliable and solid release...

[nuxnamon]

if not already mentioned, a better piano roll.. like FL..

[heavensdaw]

Multiple clip editing and selection in arrangement.
Recording automation in session.
Updates on effects.
Group within group.
Ability to open multiple projects.
waveform automation.
type in values in automation lanes.
stability.

Hd

[A Single Digit]

One thing would do it for me: clip launching videos.

[Trex-step]

here are some things that i believe would attract a large crowd to ableton:
1. Multi-colored spectrum waveforms such as in traktor or serato

2. Detachable arrangement view for users who use multiple screens such as in Reason. (effect rack, clip/pattern view in one window and arrangement/session view in the other. or vise versa)

3. Layout rearranging capabilities. ex. Drag track title columb from the right side to the left (easier to transition between other DAW's such as FL, Cubase, Protools, etc.)

It's all about the look/feel, it took me years to switch to ableton because of how different it looked from other DAW's. everything else is ace though, especially from what I've seen in ableton 9.

[oddstep]

One thing would do it for me: clip launching videos.

Live can only play one video at a time, so it wouldn't be much fun anyway. Upgrade to live suite get jitter and then you've got all the video power you can handle.