PbP is completely different from Roll20, PbP can be just like you stated. Roll20 is real time via a chatting, but if you rather not type, you can do voice and if you use Skype, you can even add in video.
I'm big on city adventures and intrigue and plans withing plans, but not exclusively. Not interested in anything zombie-centric or 'men in ships' Sci-Fi. Currently in online Pathfinder games: (Human Ranger/Fighter),(Human Druid/Fighter), (Human Sorcerer/Inquisitor/Fighter), (Human Magus/Rogue - Investigator). Starting to explore other systems. In a Shady Gulch/Coyote trail game (Lone Bountyhunter of the Apocalypse ) and Atomic Highway (Bartertowner Greaser with a proud NASCAR history). Would like to try The Chronicles of Future Earth (BRP).
I'm a late-40's Canuck with probably waaay too much time on his hands :). In year 2 of the re-union tour via after a 25 year hiatus from RL RPGing (due to a really crappy locale for gamer density/resources). I'm not mobile outside of walking distance so I'm limited to online play at this time. I've got Mirc, Skype, Maptool, OpenRPG and am willing to DL other software as needed. There are a bunch of us who play in various groups. Always looking for more. If you want references try looking the following folks up on PnPG games: Chrine, Apostate 2012, Layne, trialbyfireent, Gunhaven. All of these folks have sat at the same table as me for quite a length of time and know me best. Feel free to talk to any of them.
"None of you understand. I'M NOT LOCKED UP IN HERE WITH YOU. YOU'RE LOCKED UP IN HERE WITH ME!" - Rorschach (Jack Earle Haley) moments after dousing a fellow inmate with boiling cooking oil in -'The Watchmen'