I use Studio One as my primary DAW. I find it to be magnificent. I appreciate the workflow because of some of the simple, but effective ways they've implemented drag and drop capabilities. Also the browser and how well it's integrated into the rest of the program is fantastic. You can use it to save, sample, save whole effects and/or instrument chains, save presets. It's phenomenal.
The included effects are fantastic as well. So many useful tools, and they are very consistent both in use and in design. And the addition of the mastering suite is great for getting an idea of what a finished album or project should look like. Very powerful tools at your fingertips with S1.
They've already announced that Studio One version 2 will be released some time in Fall 2011, so yes, there will be more to look forward to.
I've tried Cubase, Pro Tools, Sonar and Ableton and so far I find Studio One to be the best one out there for my needs. I highly recommend it.
Cheers!
- Gizz