Well FormZ has announced Bonsai 3D and Microsoft/Solidworks has 3DVia (the interface stinks).
I really like Sketchup, but I'm not the big user.
After I started my own Architectural company 1Β½ years ago I found out that our main app. had to be AutoDesk Architecture, as our main work is on the construction site, and it's our customers demand.
But I also found that Sketchup is far the fastest/most easy tool for design, better (for us) than 3DS Max we thought was indispensable as I used it in my earlier job.
All the e.g. scripts, renders that Sketchup can work with makes it at great tool, and when you see work like e.g. "Silver Shadow" it makes you realise that modeling problems comes from bad skills and not from Sketchups capabilities.
Anyway I hope that SU7 will have the high poly support, multicore support, organic modeling tools, and other stuff, so Sketchup can keep leeding the "easy modeling" race.
If not, I'm afraid that other app. will run it over and the hardcore usergroup will decrease in the future.