I've been playing Wukong almost non stop since he was released yesterday and I've been figuring out a decent build for him. This build is super expensive and also a work in progress so any feed back will be helpful.
For early lane phase i try to harass as much as possible without using all of my mana and last hitting minions as much as possible. I try not to go back unless i absolutely have to.

for runes I use either:

9 Greater Marks of Alacrity
9 Greater Glyph of Scaling Magic Resist
9 Greater Seal of Armor and
3 Greater Quintessence of Health but I have also use 3 Greater Quintessence of Gold to help cover the cost of items over the duration of the game.

For Masteries i use a 0/21/9 with points in Haste and Greed . This gives Wukong the much needed durability in early game while helping with CD's of summoner spells and an extra bit of gold.

For skills I pick up Nimbus Strike at level 1 to help push the lane. at level two I get Crushing Blow and Warrior Trickster at 3

I then max out Nimbus Strike because it is your most damaging skill and then max Crushing Blow leaving Warrior Trickster for last picking up your ult at 6, 11, and 16

When going for a kill in a team fight start by using Warrior Trickster (ill explain in a sec) Then bust a Crushing Blow on the nearest carry champion if timed right your Warrior Trickster should be doing his damage to the carry you just hit with Crushing Blow then pop Cyclone.

This should do enough damage to kill or severely cripple the enemy champion and another Crushing Blow followed by a normal attack should finish them off.

For Spells I usually take Flash and Ghost to help get away and to chase.

If you don't like or your not good at using one of those Heal, Ignite, and Exhaust are all possible options.

When it comes to items for Wukong there are a lot of options while most will take Berserker's Greaves you could also take Boots of Swiftness or even Mercury Treads.

After that comes the question of Sheen first or Black Cleaver, I usually go with the cleaver giving me an early advantage with the stacking armor debuff.

Afterwards I rush Sword of the Occult and start getting stacks up asap. Then i pick up Sheen and a Banshee's Veil.

This is were I take a look at how the rest of my team is doing and either go more tanky with a Warmog's Armor or more DPS with a Phantom Dancer.

Games haven't gone on long enough for me to get a last item but im thinking a Zeke's Harbinger or something would help there.

Pros:

Can do massive damage to carry's

Has some nasty armor debuf with Crushing Blow in team fights.

Is easy to get a bit tanky without losing and dps.


Cons:

Decoy doesn't do anything which is a dead give away when you use it

Easy to run out of mana early becoming useless early game when the other team push's

Is really vulnerable to ranged carry's during his ultimate.

Wukong is the funnest champion I've seen in a while with great potential to do great in games but is heavily dependent on items meaning if you lane with a champion like Garen or someone with a lot of AOE abilities you won't have the damage needed to go toe to toe with other champions and make you look like a total scrub when your away from your team farming minions during mid game because you are way behind.

Still love smoking AP champions with Wukong and them going WTF because they blew all there damage on my decoy instead of me.