Summary of game
PAYDAY: The Heist is a fast paced, first person shooter themed around large scale robberies and activities associated with being a crew of people capable of performing such robberies. Multiplayer is HEAVILY
recommended. Buying this game for single player is discouraged.
Each of the maps, called Heists, last around 10-25 minutes. There are random events in each map that you must adapt to. These can be minor or major, and can be the difference between succeeding or failing a level. They can range from a specific door being open to the location of a VIP to the amount of time a time based objective takes to complete. There are nine total heists. Six in the base game, one with a free dlc (downloaded automatically), and two with the Wolf Pack DLC. Only the host needs the DLC to be able to play a map. If you join someone who has the DLC, you can play the map even if you don't own it. Heists are meant to be replayed, a lot. While that may sound bad, the random events, in my opinion, do well to spice up each run. A lot of people like this, a lot of people hate this.
Do people still play this?
After sales are over and the population is stabilized, only a few hundred players are online at any given time. It's very possible to get a game going for the middle and lower tier difficulties. However, getting an impromptu game going for the higher two difficulties may prove more difficult. I would personally recommend you find a group to play with consistently.
Differences between the first and second game
PTH has maps that are of a much larger scale. The guns handle a bit different, and there's fewer RPG elements. No one will be able to tell you which you'll prefer, but I would personally consider PTH to be the better shooter.
Stealth still exists, but it's much less prevalent. Only one map can be said to be "fully" stealthed, and even then it's closer to 90%.
Gun and character customization exist in a very limited capacity. PAYDAY: The Heist has NO controller support
Guide for new players
If you're new and have questions about the game, I would recommend looking through this guide. it covers most of the basic concepts, as well as some common strategies.http://steamcommunity.com/sharedfiles/filedetails/?id=113164248
if anyone has any ideas on what else to add to this, then please let me know.