I did this guide right after the new patch from the 18th Janaury 2012, so its up to date. The main change in Shaco is that his Jitb (jack in the box) only last 60 sec instead of 90 sec, this doesnt seems to be alot, but you now have to get another jungle route, since i used to do the (2 jitb golems -3 jitb red buff - smite big wriath route). Im not a fan of taking double buff instand, guess this wont work anymore aswell, since you only can stack about 4 jitbs around.

*** Jungle Videos will be added soon ***

I recommend Smite + Ignite / Flash / Exhaust.
Ignite grants you the extra dmg you may need in Ganks and is amazing vs enemys like: Soraka , Mundo, Volibear, Swain.
Flash can increase your gankrange, because you get 2 gapclosers and is nice for escaping when deceive is on CD.
Exhaust is good if they play double AD carry or if they bring Nukers like Veigar / Le Blanc.

I myself play with Flash + Smite, because i prefer a saver way to play and i can use deceive as dmg skill and gapcloser.

I recommend this runes because: ATS is always nice and will increase your jungle speed / dmg output. AD / Armor will help you jungling alot. MR per lvl will increase your lategame sustain alot, since you always will get focused.

In Masteries i take 21 - 0 - 9 since Shaco is Assasin and should focus on dmg-output.

I start as most junglers with cloth armor + 5 heal pots, you can do it with the sword , but i prefer more jungle sustain, since you can jungle even longer, get more exp and lvl up faster. Boots of mobility is a Core Item, aswell as Inifinite Edge, since it works great with your deceive 100% Crit. Phantom Dance will give you another boost on your movement and Dmg output. And GA / Banshees Veil are great for your sustaint, since you will get focussed. After you went that far, you can sell your wriggles and buy a Bloodthirster.

Pros:
+ fast jungler
+ strong invisible ganks
+ 100% crit while gank
+ autoattacks slow
+ amazing gapcloser
+ strong early game
+ brings his private 60 sec wards

Cons:
- if he dont get kills early he has to farm alot
- such squishy until he gets GA / Banshee
- his jungleroute can be denied alot by destroing JITB's
- his ult is mostly useless when he have Buffs, since they dont show on his puppet

So this is the route i recommend to you:
Wraiths -> Red Buff -> (Gank)? -> Golems -> (Gank)? -> Wraiths -> (Gank)? -> Wolves -> Blue Buff -> (Gank)? / Counter Jungle / Base.

You place 2 Jitbs at 41 sec in the middle of the Wraiths, turn over to red and place 2 Jitbs there. Then again head over to Wraiths, since they appeared, clear the shrine place a third Jitb at red and kill red. Then you can gank with lvl 2 deceive and red buff. Head over to Golems, the wraiths, wolves, blue. I recommend to gank alot with shaco because his gank potential is really huge. After blue you can easily start to counter jungle, because its about 4:10 ingame and you are lvl 4 with double buff.

In TF its a little bit harder to play, because this is not were he shines. I recommend to you to sidepush alot, since you can join your team really fast, even faster then the enemy who splits against you so you get a 5 vs 4 in your favour position. If they dont split anyone up for you, just push their sidelanes and tell your team to play defensiv until its an even 4 vs 4. If you have to fight 5 vs 5 because you have to defend because they push: Go out of visible range, ult, send your ult in, with your team (You ult will get focussed alot), deceive over a wall and focus the enemy AP / AD carry. If you do it right you will hurt them with AoE Dmg of your ult, and single nuke enemys carry, since they dont know where you are. Thats a little bit harder if they have oracle, try to get it down before the TF starts, if that doesnt work just follow your team behind the tank and try to kill atleast 1 carry.

As said, Shaco is fast in jungle, amazing in Counter jungle and huge in ganking. This should give you alot of gold. If your ganks dont go well and you die, you have to take over lanes where your TM port back, and later on farm alot on sidelanes to push them. Shaco is actually a good sidelanepusher, since he can deceive over walls and dissapear really really fast.