I haven't been away an awfully long time in the grand scheme of things, (since just before Vel'Koz was released) but I know this game evolves fast. Anything I should know if I boot it back up and download the patches?
Well, summoners rift got a really cool visual update. The jungle is a lot tougher and isn't very forgiving on junglers without a form of sustain. A few more champions are out and a butt load of really cool skins. This game is still worth it, people are just upset about buffs/nerfs/bans/their-own-playstyle/etcetcetc. A lot of still enjoy it but the ones that are having fun are too busy playing games to answer you :P the ones that don't like it are here complaining about it XD. You're lucky I caught ya as I was glimpsing for a good read.
Oh god. First of all, dont let them tell you not to come back. Second of all.... If you do come back, prepare to have your mind fucked and imploded at the exact same time.
Don't bother, just pick up some other game. Riot doesn't deserve your time or money.
Definitely download the patches and give it a shot.
Nobody can make the decision of whether or not to play league again except you. Nobody knows whether you'll like the current state of the game or not, that's a decision you need to make yourself.
Download the patches, give it a shot, then decide whether to pick it up again or not.
The biggest changes have to be the update to the rift, and preseason's changes to drag, baron, jungle, and towers.
Oh yeah, mana regen got nerfed too, mainly for 
to not give endless mana.
Here's a link to the preseason changes: http://promo.na.leagueoflegends.com/en/lol-preseason-2015/
Shrug
Shouldn't be too hard to pick up where you left off unless you want to jungle.
Dont even bother coming back. This game is getting more and more of a pain in the ass to play.
