Several Feats are missing a large chunk of their text
 

True Arrow Style being the first one I can recall.

Prereq's: Dex 13, any martial class
Arena Fighting
Heroic Tier
Benefit: You gain a benefit with any of the following exploits you possess.

Appears In: Dragon Magazine

The problem is, it forgets to list the benefits and the exploits.

There are a few others... mostly Arena feats though.

Not just feats, also powers. I keep the compendium on-hand when I level up, since chances are anything with a trigger has lost that trigger on import. Might it be a quirk similar to the one that causes monsters to lose ability triggers when you open them in Adventure Tools? (Seems like dodgy databse entries to me. HeroLab has an excuse, since it has to work by scraping. WotC does not! >_<; )