Basically, the Spellcasting Prodigy feat causes a Spellcaster's primary spellcasting stat (Int, Cha or Wis depending on class) to be considered 2 points higher for purposes of determining DC's and Bonus Spells. It can only be taken at first level.
The screaming and howling comes from those people who feel that there is no reason for any spellcaster to not take this feat at first level. I think this is a load of bollocks. As a spellcaster, there are plenty of feats that are great to have (Spell Focus & Greater Spell Focus, Spell Penetration, Improved & Reactive Counterspell, Armored Spellcasting, Quicken Spell, Empower Spell, the Craft Magic Item feats, etc.) but since most spellcasters don't get many feats, they have to really choose them carefully. While this feat may help out low to mid level spellcasters, it's value tends to drop off dramatically at higher levels when you wish you had taken Spell Penetration instead.