Destiny patch 1.0.2 is now live, which, among other things, ensures that now the Cryptarch vendor will now always reward you with Legendary quality items or better for Legendary (purple) engrams, putting the reward better in line with the engram’s moniker.
Rare (blue) engrams will similarly always produce rewards of at least Rare quality. They also have a higher chance to drop Legendary gear than previously. Legendary and Rare drops have also been added to the potential rewards for more of the strikes and missions, ensuring that everyone should be seeing fancier drops in the coming weeks than they have thus far.
The update includes a number of other tweaks and fixes to gameplay which you can check out here.