Recs.
Updated
SpecsUpdate
Pros
Pro Insane multitasking requirements
The faced paced gameplay (especially in the newest expansion: Legacy of the Void) means you will always be challenged. You will need to manage many things all at once - preparing for your next attack, planning your next expansion, managing your economy and supply, scouting, and about a dozen other things as well. Even when attacking, you need to zip back to your base to keep your economy, ensure you have enough supply, and start training up new units for your next attack or defence against any possible counter-attack.
Starcraft II will make you feel 10 steps behind, even when you're winning. If you want a demanding, multi-tasking heavy game to play, Starcraft II is everything you're looking for. When you do manage to perform well, it's a very rewarding feeling.
Pro Build order mind games
In competitive tournaments, the finals are best of 7. This results in some game theory because you have to try
to figure out what strategy to do. Basic strategies in Starcraft have a sort of rock paper scissors relationship, so you can't just do the "best" strategy over and over. The strategies balance greedy economy, which is good in the long run vs short term rush strategies. This is actually very similar to real war.
Pro Requires lots of micromanagement but cannot forget macro management
Of course you need a general strategy on how to evolve, and for that you also need to scout, but then you also need to perform lots of actions to manage all of your troops (all the time) in order to be more likely to win battles.
Cons
Con Can be stressful to lose
The amount of effort required to win a game (at any skill level) is unprecedented. Losing when you pour your heart into any match could be discouraging to some players.