While some heroes had their abilities reduced, numerous others were given new abilities or had their existing powers retooled, continuing trends set last year with the 6.81 update, which introduced additional skills tied to in-game item Aghanim's Scepter.
Valve has also added eight new items to the in-game item shop, with an apparent emphasis on new kinds of item progression for games that go longer. This is likely in response to the increase of game time presented by the last several Dota 2 updates, which in turn has exposed certain characters lower power ceilings in comparison to others. Reactions to the patch notes seem hopeful that more characters are more viable later in longer games, opening up Dota 2's hero pool for competitive play.
But Valve's changes also include a scaling back of the colloquially known "comeback mechanic," a set of formulas that change the amount of gold and experience awarded to heroes depending on their levels and the worth of their in-match gear. Complaints have been building in the competitive community that the previously standard system amounted to a rubber band that punished winning teams for their later mistakes too severely.
Today's patch is expected to establish a new baseline for Dota 2 in advance of TI5. Meanwhile, TI5's "Compendium," a virtual program for The International Dota 2 Championship, part of whose proceeds will go toward the event prize pool, is expected to go on sale soon.