Moving away from what Smurf's strategy might be ... several thoughts on several Pokemon in the UU metagame.
Venusaur - I'm tempted to change my mind on Venusaur's tiering. It just has so many things going for it. For a sweeper its bulk is excellent, it has instant recovery, it has a sleep-inducing move and its Leaf Storms are only a little weaker than Sceptile's (100 SpA vs. 105 SpA). It can run a multitude of different sets. It's indeed walled by several Pokemon, and to quote whistle's list in QC, these are "arcanine/moltres/altaria/drapion/registeel/weezing/scyther/clefable". Arcanine, Moltres, Scyther and Altaria are all weak to Stealth Rock, two of them dangerously so. If Stealth Rock is up they might even risk dying to Sludge Bomb on the switch. Registeel, Drapion and Weezing don't have reliable recovery outside of Rest, but Venusaur can recover its health, so all three can be worn down eventually (and RestTalkers have their own problems). Specially defensive Clefable walls Venusaur alright, but it's only one Pokemon and it can't really wall other variants of Venusaur such as SD Venusaur.
Sceptile is arguably more destructive than Venusaur when it switches in, but it is far more fragile. Switching Sceptile into Milotic can actually hurt more than help. Min SpA Milotic Surf vs. 4/0 Sceptile is 21% - 24.6%, so after SR damage Sceptile is often forced to heal (if it has Synthesis). Then Milotic might have Ice Beam, which 2HKOes Sceptile easily. Venusaur on the other hand can switch in on Milotic easily, and Milotic the most common Pokemon in the metagame.
Back in the Froslass metagame I wrote that since Froslass can set up on Venusaur (who was the most common Pokemon in the metagame then), we should expect Venusaur use to decrease. Since it didn't, the logical conclusion is that Froslass isn't as dangerous as some people made it out to be. Although this is logical, and although it is similar to the Venusaur <-> Milotic case here, it does have a flaw. Milotic is a fantastic defensive Pokemon that is a one-Pokemon cure to so many of the metagame's threats, from Moltres to Houndoom to Blaziken to Rhyperior and the list goes on and on and on. The same can be said of Venusaur during the Froslass era as well. I believe many teams think the risk of using Milotic, and therefore letting Venusaur switch in safely, is well worth the gain.
Venusaur is much easier to handle once you know its set, and there are combinations that Venusaur simply cannot muscle its way across. But even if Venusaur can't scratch a team, it still has Sleep Powder, so it won't ever be dead weight. So like I said, I'm tempted to change my mind on Venusaur's tiering. I used to think it's UU, and even now I don't think it's overwhelming, but it's at least at the top of the UU hierarchy.
Milotic - this Pokemon sure walls a lot of things. So many things are walled or at least checked by Milotic. The list just goes on and on ... Feraligatr is checked, Moltres is checked, (Specs) Blastoise is checked, Rhyperior is checked, yada yada is checked, etc. I've found that when I use Milotic, everyone and their mothers tries to beat it Toxic'ing it. But even though that means Milotic will not be able to wall a Pokemon ad infinitum, it can still check Pokemon like Rhyperior and Donphan easily, especially since it has Marvel Scale active. There're even Pokemon like SpD Arcanine who've been developed specifically to beat Milotic.
What more can I say about Milotic? It walls a crapload of the metagame. It can survive hits like Magmortar's Thunderbolt, which is 95 BP + super effective + 125 base SpA, so it can function as a last-ditch check to many Pokemon. It has respectable offenses for a wall; I've had several games already where it came down to Milotic vs. Milotic because neither side could afford to switch out. It even walls (some variants of) Heracross, despite Heracross being a formidable physical attacker hitting on Milotic's weaker side. I suspect that if the tables were turned and Milotic were actually a sweeper that sweeps as many Pokemon as it currently walls, Milotic would be an easy BL. So much for the difference between the offensive characteristic and defensive characteristic.
There're still things that beat Milotic, but for now I'm inclined to agree with Eo's assessment that Milotic is the best Pokemon in UU, better even than Heracross. BL it isn't, but only because defensive Pokemon are always going to be vulnerable to set-ups.
Ambipom - This is the most common lead in UU right now, and one that I don't quite understand. It beats many leads, yes, and it has free damage every time it switches in. There are leads that handle most other leads, bar Ambipom, and there are leads that carry Protect just to beat Ambipom ... but so what? Ambipom has its hard counters. Without Pursuit, ghost types can easily switch in and score a strong hit or maybe put up a Sub. Even with Pursuit, Spiritomb is a 100% counter, and it's not hard to switch it in unharmed. Just switch in on the Fake Out and gogo Pursuit. Spiritomb takes no damage and deals big damage, what's not to like? Even worse for Ambipom is that it can't do anything about Spiritomb switching in unless it has prior knowledge about the team it's facing, and even then not using the "free" Fake Out is a gamble. Ambipom is dominated by Spiritomb as badly as Alakazam, in fact it's dominated even worse than lead Alakazam because lead Alakazam might have a Sash / Reflect to save itself from Spiritomb. Yet to my knowledge nobody has mentioned Spiritomb in relation to Ambipom while Alakazam's Spiritomb weakness is consistently brought up.
That's not all; there're other hard counters like Steelix, Registeel and Regirock as well. Unless Ambipom has Low Kick (and even if Ambipom has Low Kick, it can't 2HKO), it's stuck in the awkward situation of "should I Taunt and risk getting attacked, or should I U-turn and risk SR going up?". It's even more awkward since Ambipom is supposed to stop SR going up in the first place. But all these problems haven't stopped Ambipom from being consistently among the top UU leads.
I'm curious how the players who use an Ambipom lead deal with the chance that the other team has a Spiritomb / Steelix / Registeel / assorted Ambipom hard counters, because personally it means I've simply stopped using Ambipom leads @_@
