Just as a heads up, they're completely revamping the out of game stuff in heroes of the storm, dubbing it heroes of the storm 2.0. Its less money based, and more F2p style... including chests that you can earn with rewards.
Before, each hero, once bought, could be leveled up to earn different skins, along with a master skin only available to buy once it was level 10. All other skins had to be bought with real money.
Now, each level you earn can get you a chest, and each chest can unlock any skins/colors, which you can equip. Along with taunts, voice packs, banners, mounts, etc. Its basically a way to reward you for keep playing and getting lots of cool new unlocks.
They're also launching with a new hero, Genji, and an Overwatch map (hanamura) which mimics payload matches.
Theres also 1 more hero coming (rumor is DVA) around launch.
One cool thing, and the reason I bring it up? During the 2.0 launch event, they're doing 4 mega bundles:
http://us.battle.net/heroes/en/heroes20/megabundles/Each bundle costs 100 gems (new currency), and comes with 20 heroes in them. You can only buy one of the 4 mega bundles. Also, logging in during the event gives you 100 gems for free! Meaning, they're gifting you 20 heroes just for checking it out during the launch.
Well worth checking it out during the launch event, especially with all the overwatch stuff coming that I know you guys are hyped on lol.