Id say back up all your data and hope for the best ^^

every once in a while, there would be a line on my tv as well, its kinda splits the screen in half when I try to move in different directions in the game, but its nothing serious, all I need to do is turn off the tv and turn it back on then its gone, did you try turning off the tv?? it would be the same problem, nothing wrong with your ps3, just some unkown minor issues with the cable/tv.

Like I said, every time I turn off the PS3 and turn it back on it seems to go away. Maybe when doing that (I turn it off from the back) I nudge the HDMI a bit.

The person from Game N Trade told me on the phone that it could just be a cable issue.

hopefully it is just a cable issue! i'm not sure why because there's no moving parts, but cable problems are more common than some might think; I have lost count of the number of USB printer cables that have just stopped working (without any obvious signs of damage to the cable) mysteriously.

anyway, be careful about using the PS3's inbuilt backup system as your only backup system; remember your backup will be of no use to you at all if you try restore to a different PS3 than the one you backed up from. try to save as many unlocked saves, movies, vids and pics that you can to an external HDD too, just in case. (speaking as one who has recently been a victim of a fatal YLOD, you can never have too many backups :) )

safest but most expensive option is to get a new slim PS3 and do a PS3-PS3 transfer, but you'll unfortunately not have the old info on your old PS3 anymore as it would have been moved to the new PS3, and you lose out on the tasty goodness of the phats PS2 b/c, unless you keep the phat around and only use it on special occasions lol.