Gdkitty is correct. Your usage may vary on a daily basis. This could be due to multiplayer gaming activity, gaming updates/patches that needs to be downloaded, system patches/updates that needs to be downloaded, if you buy your games online instead of on disk, streaming video service, etc. Some of these items will only range a few hundred megabytes, and could scale up to gigabytes or more.
If you are just doing multiplayer gaming, its typically safe to say that you may use only a few hundred megabytes a day. It's recommended that you keep track of your usage on a day-to-day basis using the usage reports that Rogers gives you.
I do a lot of multi-player and online gaming on my PC, with games like COD Ghosts. My internet data usage is very low, certainly not GB's per day. As others said, probably a few hundred megabytes tops, and that's playing for a few hours a day. Unless the PS4 is very different, I doubt you'll notice a lot with it either. I also have a PS3 and have done some limited online stuff, but mostly downloading new games. Of course, downloading games is a totally different thing and your usage will be lots of GB's. I find games tend to be in the 25 to 30GB size range. On the PC side, I get most of my games from Steam and automatically get game updates as they are released.