Avid SL user here, I sustain my self inside SL using poser, but all I can (or will do)  is to make various art pices that I sell, work good thus far, not rich but I get along :) secondly I make animations with poser for SL, this is tricky and time consuming but rewarded at times with sales. I have tried just for fun to PhotoShop some poser skin textures but find this process to be way to time consuming to be worth the headace, a face is simple but a full body texture is much harder work to make it look good. There is some really good UV maps for PhotoShop with all the seems and alpha layers etc if you like to tackle it.

A note on animations, since the poser avis ( you can dl them for poser)  are as stated above low poly you can't make the animations as detailed as you can in Poser, I.e no expressions, no finger movements etc, so if you will try to make animations for sl only use the SL avis when making animations for SL. 

Ps/ don't forget to stock up on valium , becuse your nerves will bolt on you ;)