i heard hybrid is better

Okay, I just played my first game with this build. Can definitely see the pros, despite the fact that my team didn't understand Teemo's status as a split pusher and began griefing me/throwing when they perceived that I wasn't acting for our benefit. How am I supposed to react to situations like that? I kept pushing, but the game was unwinnable... what situations are there in which it's ok for Teemo to participate in a teamfight? 

A good Teemo is in every teamfight, but not actually IN the teamfight. You should try to predict the occurrence of teamfights and set up a cozy area for your team beforehand. For example, if the enemy team took baron because your jungler was not able to steal it, chances are mid lane will be pushed by their entire team. You can shroom near your mid tower and around jungle entrances. Or you can shroom around baron then force a fight in the area (taking baron, or just having your whole team in the area as you destroy a sight ward, in fact, having your entire team disappear and sit around will cause the entire enemy team to check baron if they forgot to ward). Even a failure to predict the exact location of the teamfight is okay, because after your team is screwed over 4v5, they can bait the enemy team into top lane or a nearby shroom cluster to escape

What about the auto-attack Teemo build? Beserker's Greaves (Furor), Malady, Wit's End, Runaan's Hurricane, Liandry's Torment, Rylai's Crystal Scepter. What's wrong with it? Why do people prefer AP Teemo over auto? Is the extra damage on the blind worth the slower pushing potential?

The most annoying thing about Teemo is not the fact he can chunk your health in direct combat. If you want that, pick a real AD carry, not the guy with AP scaling on all his abilities. The most annoying thing about Teemo is stepping in his shrooms while juking or traveling between the lanes or ganking. The second most annoying thing is Teemo's godly poke. AP Teemo Q can chunk like a low level Nidalee spear, and Teemo's Q autoattack combo can leave some of the squishier champions running to a bush to recall (the unwarded bush that Teemo has been screwing around in ;). 

Also, AD Teemo has a 100% AD scaling on his autoattacks, but AP Teemo has 110% AP scaling on autoattacks (AP scaling oon chapion autoattacks is 40% and you have to add the 70% from toxic shot, also I did not count the base damage from toxic shot's initial damage and Dot so the number is more thn 110% actually). Note that this AP autoattack scaling only occurs if you space out your autoattacks

Holy shit. Ok. AP Teemo is king.

Ok first of all my AP teemo build is so dominating cause each of my mushrooms do over 1000 damage (not extra zero) to some one without much magic resist so plant all three or just two in a bush bait 2 of them after you and boom double kill and if you aint shore you will get the kills stay close and let your passive kick in and then you git +40% attack speed for 4 seconds and you just dominate but soon they will learn there lesson not to chase a good AP teemo next time.  But if they all chase you just run through your jungle and your passive on your W will get you out of most fight you don't they you can win.

OMG, I never was played mid before and when i do i go as Teemo and just evaporize the enemie Talon. This build is the best ever from far.

I don't think its a good idea to play Teemo mid. Mid is the easiest lane to play, because it his hard to gank, easy to push, and easy to get back to your tower. An environment as optimal as this is meant for champions who are extremely farm dependant, scale really hard, or at the very least counter those types of champions. Teemo should go top because his late game isn't too impressive, and his main enemy is burst and spell reliant champions (they don't care about the blind). Champions who mid usually have high burst (just one poke... OH GOD) and usually outrange Teemo (just one minion... OH GOD), which puts Teemo at a disadvantage.

Eu West ??

teemo op top !

Is liandry's really still worth it? I find that because the proc doesn't happen on hit, and only on shrooms it rarely has a chance to apply (except when you know someone walks through the 100 shrooms I have on map), I ran a build of Zhonya's (Was situational because of fiora),Rabbadon's,BOTRK (for the on hit and because of tanky champs),Ruunan's (I know it's not a super great item but the wave clear made it super easy to split push during mid-late), Sorc shoes, and Malady. I was able to duel/chunk people and split push really well because of all the AS boosts from the items it put me at 2.46 AS. Just wondering what the thoughts were on Liandry's gold->worth.

Liandry's is worth it. Blinding dart applies a weaker version (6% burn), and stepping on one shroom will instantly proc the super version (12% burn for those tanks). I really doubt Teemo should get BOTRK because AD Teemo really screws over his potential shroom damage. Think about it this way: AP Teemo's autoattack is a burst with a 4 second cooldown (to give maximum E damage). I like to buy Runaan's Hurricane myself as it gives me extreme presence in a teamfight and allows extreme wave clear, but I doubt very skilled players would suggest such an item.

the BOTRK wasn't really for the AD as much as it as for the 5% health chunk plus the active, which I know sounds like a waste of item space but with the attack speed i ended up with i was pretty much dropping people to 50% in a matter of 3-4 seconds and since ruunans applys the on hit from it, it gave me a little bit of presence in team fights if i absolutely had to be there. I usually would pick up nashors instead of botrk.