Riot doesn't think so. Here is a list of past changes:
V4.5:
Stats
Base armor increased to 21 from 17.
V4.2:
Unspeakable Horror
Now causes target to flee away from the source at reduced movement speed.
V3.14:
Duskbringer
Fixed a bug where the trail bonus was applying inconsistently.
V3.02:
Paranoia
Fixed a bug where Nocturne wouldn't automatically chase his target.
V1.0.0.152:
Stats
Base movement speed increased to 345 from 320.
V1.0.0.143:
Umbra Blades
Tooltip updated.
Shroud of Darkness
Shield duration reduced to 1.5 seconds from 2.
Paranoia
Cooldown increased to 180/140/100 seconds from 160/130/100.
V1.0.0.140b:
Umbra Blades
Heal per target hit adjusted to 10/18/26 from 15/20/25.
V1.0.0.139:
Unspeakable Horror
Fixed a bug where the Ravager Nocturne was not visually applying the fear tether.
V1.0.0.135:
Umbra Blades
Now displays a cooldown timer.
V1.0.0.129:
Unspeakable Horror
Cast range reduced to 425 from 475.
Leash range reduced to 465 from 525.
V1.0.0.125:
Unspeakable Horror
Leash range reduced to 525 from 550.
V1.0.0.123:
Paranoia
Nocturne will now attempt to attack the target after using Paranoia.
Paranoia no longer grants assists for limiting enemy vision.
V1.0.0.121:
Paranoia
Added minimap range indicator.
V1.0.0.118:
Duskbringer
Base damage reduced to 60/105/150/195/240 from 60/110/160/210/260.
Paranoia
Base damage reduced to 150/250/350 from 150/300/450.
Fixed a bug where it caused a glitch the first time it was used.
V1.0.0.116:
Paranoia
Fixed a bug where it would follow targets over variable amounts of distance depending on spell rank.
V1.0.0.115:
Duskbringer
Attack damage bonus reduced to 15/25/35/45/55 from 20/30/40/50/60.
Unspeakable Horror
Cast range reduced to 475 from 500.
Leash range reduced to 550 from 600.
Fixed a bug where breaking the leash near the end of the duration would still trigger the fear.
Fixed a bug where adding a spell shield like Banshee's Veil while the leash was active would block the fear effect.
Paranoia
Dash range reduced to 2000/2750/3500 from 2500/3250/4000.
V1.0.0.114:
Shroud of Darkness
Shield is now brighter and easier to see.
I count 13 nerfs, and ZERO buffs. (the armor and movement speed increases were changes made to all champions, so not buffs). Everything else is just a bug fix or a clarity thing. I seriously doubt Riot will ever be buffing this guy.