Quote from Blizzard

You might have been part of helping us test the new balance changes coming to StarCraft II, and these most recent adjustments will be coming to the game very soon. What’s different is that, for the first time ever, they won’t be applied as part of a patch.

On May 10, after a brief maintenance period in each region, the following balance changes will take effect globally:

Quote

Protoss

• Observer build time decreased from 40 to 30 seconds

Zerg

• Overlord movement speed increased from 0.4687 to 0.586
  
• Queen anti-ground weapon attack range increased from 3 to 5

Again, to be clear, these changes will take effect after a short maintenance in each region is complete, and neither a patch nor any other special action will be required to experience them in-game.

Thank you for your feedback, and see you on the ladder.

Source.

Update:
In addition to that, the queen's ground attack animation is now her anti-air attack launching a projectile. This means that Queens can potentially overkill an enemy unit and be stopped by Raven's point defense drone.
Her ground attack remains upgradeable via Zerg Missile Attack Upgrade.
Source.

Update:
Queen launches 2 spines as ground attack.