To answer my own question.. I began most heavily using the Palladium D20 based system. It pretty much dominated all our gaming sessions. We tinkered with many others but Palladium was most prominent. (There were no mini's, no maps, just dice, pencil and character sheets.)
So generally for me after characters are made (usually done first, but not always), we'd begin with a question period to let players clear up last minute details and correct anything on their sheets.
I would give a sort of OOC description of how the group got together or set the stage for why they were about to meet IC.
Then I would let them ask some questions about the physical environment.
Once we'd worked through a lot of the OOC general stuff then I'd begin much the same way as the books "intro" describes setting the stage. I would get into character as the GM and begin a colorful explanation of the weather, day/night, usually I liked to start them in a bar/nightclub/tavern etc... Then I'd move on to describe the action and the general IC motivators as the scene launched. Like narrating a book as the NPC's move through the scene.
After that everyone got a chance to shuffle themselves around by narrating their own characters into the scene and beginning to engage the environment. I never let them go to far though because I wanted to make sure that all the others had a chance to do the same. (I personally found it would influence more detailed actions in the next round.)
As for forum RP, although I do mostly freeform or semi-freeform on E. I noticed that I like to open my group games the same way. It feels right to me, a comfortable learned pattern.