Welcome Back!! 

As I recall, you're pretty adept at learning new things and adadpting quickly. With that in mind, why limit yourself. Poser 9/2012 is on 50% off sale, and DS4 Pro is free - Get them both and don't look back.

Poser has some great new features, and DS4 has it's own set of great new features. As you will learn, there are some people who seem to feel that the two programs can no longer co-exist. Others that feel DS4 simply is not usable with the new interface (it took me maybe a half hour to get over the new interface .... others mileage will vary), or that the new content manager is evil (give it a test run to form your own opinion). Many will even say that Genesis is a horrible, low quality figure, and none of the old content works with it (actually, a great deal does work with it, and with DS4 Pro free, the included CCT preserves all of the original morphs). Of course there are others that will say all the old figures are dead, Genesis is the future - the truth probably lies somewhere in the middle. Again, I would encourage you test drive and form your own opinion. IMHO, Genesis with the proper morph sets is simply awesome, nothing else currently available on the market comapares in versatility. But from what I've seen,  weightmapping and SSS in the new Poser (something that is loooong overdue) is also **very **compelling (hoping to get it while on sale).

As for how many people are using Poser vs DS**, nobody** really knows. Probably the best source of info is the poll being conducted by 3D Universe, which right now has  Poser 9/2012 at 30.4% of all responses, DS4 at 30.38%, Poser 8 or older at 15.65%, and DS3 at 9.21%. With the divide created by the differences in weight mapped technology in Poser 9/2012 and DS4, and DS4's support for Catmull–Clark subdivision, unless the two decide to cooperate soon, figure vendors will be faced with either developing multiple versions of the same product (i.e. Genesis and V4), supporting older products/technology exclusively (V4, etc.), or specializing in one platform. Until things stablize a bit, I think anyone looking to get into content creation really needs to either 1) focus on which of these two programs and new technologies they really feel most comfortable with or 2) learning to develop for both.

I know this probably isn't the answer you were looking for, but the best advice I can give is to take the bit of insight given by the 3D Universe poll, try both applications yourself and see what you like and don't like about them. Then make your decision based on your experiences (remember, DAZ gives a 30 day money back gaurentee, so you can try the Genesis morph paks out, and if you decide you don't like Genesis, ask for your money back). 

Good Luck!!!

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