With Christmas over, many video game fans have received a PlayStation 4 console to replace the PlayStation 3. However, users may have been impatient and bought several of the blockbuster PS3 and PS4 titles and wish to upgrade to the new console. Fortunately, several titles are part of a PlayStation 3 to PlayStation 4 upgrade program, so users won't need to buy the game again for their new console. Here's a guide to Sony's upgrade program. 

Only a few games are available as part of the upgrade program: Battlefield 4, Call of Duty: Ghosts, Assassin's Creed 4: Black Flag and Injustice: Gods Among Us. In the physical copies of these games, there is a code that will allow users to get the next-gen version of the games. Once players set up the PlayStation 4, they can access the PlayStation Store and go to the PS3 to PS4 category. After selecting a game, add it to the cart and make sure you're being charged $9.99 for the upgrade as opposed to $59.99 for the full game. Then you can purchase the game and if you own the digital version. The game should then update itself. If you have a physical copy of the game, once you buy the upgraded version of the game from the PlayStation Store you just need to insert the disk into the PlayStation 4 and begin playing.

However, if you want to switch from the PlayStation 3 version to the PlayStation 4 equivalent, you only have a limited amount of time. For Battlefield 4, the offer to upgrade the game to the next-gen ends on March 28, 2014. For Call of Duty: Ghosts, Assassin's Creed 4: Black Flag, and Injustice: Gods Among Us the offer ends on March 31, 2014.

PlayStation 3 owners who have upgraded to the PlayStation 4 or are planning to do so when Sony gets more copies of the machines out to consumers should take advantage of this offer.