Legendary item buffs in patch 1.0.4 look good!
In a blog post today Blizzard revealed a bit more about their upcoming rework of the legendary system. They are both buffing stats, adding more effects and spiffing up the look of the items. It looks like all weapons gain some sort of particle effect, which is pretty awesome.
What is pretty awesome, is that they are actually making weapons, that people would want to build skill builds around:

Ranged barbarian? Apparently possible with the legendary buffs in patch 1.0.4 with buffs to the legendary weapons.
And don’t worry if you have already learned legendary recipes. They will update automatically, if they are buffed:
Anything else, would have been a dick-move by Blizzard. However, do be aware that legendary items will not be buffed retro-actively. This includes non-IDed items as well, since stats are determined on drop, which we saw with the recent Diablo 3 unID exploit.
All in all a pretty interesting read well worth checking out on the official Blizz forums.
Can we bet legendary receip going up if new item they provide are realy nice, can it worth speculate in it
The craftable legendary will only get a change : the weapons will have a chance to roll for dps as high as lvl63 weapons. So yes the legendary weapons are somehow buffed but we don’t know yet the probability of getting high dps.