I'd list three things I really like.
The snappiness of a 64 bit app.
The ability to use lots more memory.
The multicam window now remembers that I have the Preview pane turned off, so when I close the window and open it back up, Preview is still off. (Yeah!)
I would say the Mercury Playback Engine is the best feature.
Second place is dynamic linking ability... except mine doesn't work very well. For others it is awesome!
Those two alone BLOW Final Cut and any other similarly-priced program/suite out of the water! Final cut is about 2 years behind the competition! SOOO glad to be on Adobe!
For me, it's the cool Splash Screen!
Actually, some biggies are:
- The ability to structure a New Sequence by the New icon from the source material
- The ability to alter the Duration of Imported stills en masse, without having to Delete, make the change, and then re-Import
- 64-bit program on a 64-bit OS
- With its release, we got several great Adobe folk around these parts!
Having seen CS5 develop, and use it every day, I'd have to say that the single biggest aspect of CS5 is 64-bit native application and what that means to performance.
People love to talk about the GPU and UltraKeyer and dynamic link and smooth workflows and they are without a doubt all very good. However, the 64-bit nature of Premiere Pro and After Effects make all of these other features even better. I will comment to audiences when I am presenting that if we had just done 64-bit and nothing else, CS5 would have been a success. The fact that we did that AND added all of the other goodies makes for one suite (sorry!) release.
My two cents,
Others have already mentioned the items I have in mind but I here they are anyway:
1. Hardware accelerated MPE making for smooth previews without the need for rendering.
2. PPro and AE are 64-bit - addresses more memory.
3. Rotobrush on AE saves time when doing rotoscoping.
4. Stable... I got Production Premium just after Adobe released the 5.02 patch and I can't recall ever encountering a crash.
5. Wide range of inputs are accepted/supported which means no more transcoding for me.
6. Wide range of output/export formats... I especially like the export to Vimeo and YouTube presets from which I could then tweak for either file size or video quality optimizations.