Malzahar worth picking up?

Yeah sure, why not. Some of the easiest farming in the game, relatively immune to assassins, and can pick any champion, tank or squishy, and one combo them to death.

Maybe wait till his update around may to decide?

Fuck yes! I main malzahar and I about cried when I saw they were coming out with this skin. He's amazing!

He is not bad, Qss and cleanse are his biggest counters as any time he lets or uses his E they can either cleanse or Qss out of it

He's the highest win rate mid laner right now... so odds are he'll see a nerf sometime soon, but he'll probably still be in a really good place for solo queue.

Malzahar works in solo queue because his weakness is early ganks. Oftentimes the enemy jungler won't focus you for being Malzahar in solo queue (because he'll be queued duo with another lane, or doesn't know, or another lane is struggling, etc...). Malzahar can push lane really easy and can outtrade most champions, all without running low on mana at all. Once he hits 6 he can pretty much freely kill most lane opponents.

Definitely a worthwhile pickup for solo queue, especially if you're used to playing immobile champions. His single target AND AOE damage outputs are insane. His ult is incredibly useful if you can wait until most enemy CC is gone before using it on a carry (preferably one without QSS).