No...
If those effects had been good to go for a release, they'd have been released.
The fact that they are not, means that they probably are not ready, or might be making the game to 'heavy' to run on lower end machines.
And is your computer good enough to even run SS08 with all the goodies on? If not, you may just be missing out on some eyecandy due to that reason.
But anyway, developers usually have lots more to 'play around' with, to test, to develop, etc...
But not everything makes it into the game (at the first go). That's just how it is. They will surely not leave out anything that could appeal to their customers and make the game better, trust me.
Why keep it to yourself to play with, if you can play with it just as good when it is released? That would make no sense.
So no, the creators are not leaving this out on purpose to have a better game than you do..
Regards,
Fred