I would like to discuss your working experience with Premiere Pro CS4, because I finished last week my first project in Premiere Pro and After Effects CS4 (ok the credits are missing and some details, but it's almost done) and I humbled into a new experience of working with Premiere Pro. I really would like to hear which problems you faced in working with PP CS4.
Anybody wants to share his experience too?
My editing system:
4GB DDR2-RAM
2.64Ghz Intel Dual Core
500GB 5400rpm harddrive
512MGB GFroce 9400M GT
(laptop)
Basic Editing:
I have to say that I really see improvement from PP 1.5 to CS4. It's far more stable to work with dvd source (scripts) and mjpeg files. I tried PP 1.5 on my new laptop and still had the same problem: When I scroll too much threw dvd-scripts it just shuts down all of a sudden. It was ok for my old pc, but this isn't acceptable for a new rig. In CS4 I never had this problem. Working with 720p MJPEG files as replacement for a 720p x264 script working GREAT. I mean I never had a single crash. There were no RAM problems. As far as basic editing goes: Perfect.
I also loved to use the benefit of multiple sequences with different framerate and ressolution in one project file. As far as I remeber this wasn't possible in 1.5. For example: I used a 60fps sequence to edit the audio. Which is far more precise than editing it in the original 23.976 fps project settings. (I know that there are far better programs to edit my audio, but I like to edit it in PP due to the good handling).
Advanced Effects (importing AE compositions into your PP timeline):
I was SO excited. Just a right click on a click in my timeline and I was able to edit the clip in After Effects. PP 1.5 had the same function, but it wasn't compatible to my older AE version 7. This time I had PP and AE CS4 and that's why it worked

In the end this is an "ok function" for me. I still prefer to render out clips, edit them in AE and put an effects clip on the timeline. That suits my editing style and workflow much more. There were hardly any situations where I needed only the single clip or bunch of clips with effects.
Overall there were more problems than benefits for me. First off: You can't use this function if AE isn't already open. It would crash. However if AE is already open than it works really smooth.
It really hurt the stability of Premiere Pro to use this function. Everytime I open the project there will be also an AE working process be started in the background. This one crashes randomly with a nasty error message an uses additional 250MB RAM. This process will be also opened if you don't even use the composition in the timeline. The idea of using AE comps in the Premiere Pro timeline is really good, but far away of being stable. It causes more problems than benefits.
For importing Photoshop layers there will be also a Photoshop process be started in the background, but this one works perfect with no errors.
Render Progress (Media Encoder):
Oh my god. The Media Encoder is great for batch conversation, but fails on so many levels. I really want my option of the simpel rendering interface of Premiere Pro 1.5 back!
You really don't want to stress this Media Encoder with x264/720p scripts with filtering.
If I rendered in Lagarith: The clip crashes at one frame. The rest of it is fine.
If I rendered in Uncompressed or Huffyuv: There was frame shivering and random green artifacts.
The script also was delayed by 2 frames wich fucks up the sync without Trim(2,0)

Maybe I shouldn't blame the Media Encoder for everything. It still worked good with Lagarith copies of my source (75GB for one movie weeeeeeh!) and still worked with filtering scripts for the lagarith version.
Before you finish your project you better know which settings your Media Encoder can handle. 720p x264 scripts were too much for mine, but it worked for 848x480 lagarith files with no problem. The sequences with different ressolutions made it easy to copy+paste my main sequence into it and just adjust some zoom parameters and stuff.
What bugged me was the ImporterProcessServer.exe Process in the background. It often didn't let me to change my script filterings while Premiere Pro was open (even if the project file was closed). Sometimes this process didn't shut down with PP. So I had to terminate by myself before I was able to change my filtering changes.
