Who is Wickd?
Wickd is a pro player who plays top lane for CLG.eu. He is very famous for his Irelia play. Recently on his stream, he's been playing and building Irelia differently than usual. Recently at MLG Dallas, Wickd used his non-standard build in a game against Team Solomid. Some might be interested in it since he used it in a tournament game.

How is this different from normal Irelia builds?
Normally, Irelia players build Doran's Blades, Trinity Force, Mercury's Treads or Ninja Tabi, Guardian Angel, then other tanky items. Since you're autoattacking while using Hiten Style and you get Trinity Force procs, she does quite a bit of physical damage. With this on-hit/aspd build, your early items are Ionic Spark, Wit's End and Berserker's Greaves. You can still build tankier later and get a Trinity Force if you're fed or farmed enough, but the focus is on attack speed and on-hit.

Why does this build work?
Champions who face Irelia in lane will typically build items like Ninja Tabi, Heart of Gold, Phage, or Wriggle's Lantern. Because enemy laners focus on armor and health for laning against Irelia, they won't be rushing any magic resistance items, and that's where this build shines. Ionic Spark and Wit's End both do magic damage. With Hiten Style, Ionic Spark (and later Wit's End), and autoattacks, Irelia will be doing three types of damage while chunking people insanely fast with Hiten Style.

Runes
Greater Mark of Attack Speed: Self-explanatory for this build.
Greater Seal of Armor: More survivability.
Greater Glyph of Magic Resist or Greater Glyph of Scaling Magic Resist: More survivability.
Greater Quintessence of Attack Damage or whatever: In the event your laning phase goes poorly, AD quints help you last hit under your tower with Bladesurge (among other things). Can really use whatever though.

Masteries
Whatever you normally use on Irelia. You need 9 in offense for Alacrity and Weapon Expertise though.

Items
Starting:
Early: -> + -> -> or
Replacements: or
5th/6th: zeke's herald
Trinity Force vs Frozen Mallet: Trinity Force is a very mid game-ish item, and you already spent 4k gold on your on-hit/aspd items. If you have good farm or you're incredibly fed, upgrade the Phage into Trinity Force. If you're not, upgrade it into a Frozen Mallet instead.
Ionic Spark vs Wit's End: Imo, the flat health is more useful than magic res in lane. When laning against a magic champ, you could pick up a Null-Magic Mantle and hang onto it instead of building Wit's End first. There's a thread about this on the NA forums.