Vespiquen would be dead in a matter of seconds against the following:
~Skarmory with Drill Peck/Stealth Rock PHazer
~Garchomp with Fire Fang, Stone Edge
~Salamence with Fire Fang/Flamethrower/Fire Blast/Stone Edge
~Heracross with Stone Edge
~Suicune/Starmie/Slowbro/Swampert/Abomasnow/Weavile with an ice move.
~Magnezone/Jolteon/Gengar/Weezing with an electric move.
~Heatran/Infernape with Flare Blitz/Fire Blast respectively
~I'm sure there are more
In BL:
~Houndoom
~Kingdra with Ice Beam/Hidden Power Electric
~Honchkrow
~Floatzel with Ice Fang
~Aerodactyl
~Empoleon
~Torterra
~Blaziken
~Charizard
~Moltres
~Anything else
And you think you were safe in Uber:
~Kyogre with Thunder
~Ho-oh with Sacred Fire
~A Psychic type with access to Bolt-Beam.
But in UU, Vespiquen isn't really that counterable, unless Stealth Rock is a factor (and it probably is). Vespiquen does have its good points however, a nice STAB move that only Heracross has a better version of, a good recovery move and a Cosmic Power equivalent. Basically, the only thing that lets it down is poor typing and low Speed to compensate. I mean, Ninjask and Yanmega can do so well in OU because of their Speed offsets its typing (and the fact that they sweep rather than feebly tank with Stone Edge and Stealth Rock running rampant).
Now to Hippowdon:
In OU, nothing can counter it effectively, except bulky water types and possibly Gyarados. Hippowdon is only hindered by Water, Ice and Grass moves (compared to Vespiquen: Rock, Ice, Electric, Fire, Flying). Most of these moves are special however, and Hippowdon can do little to prevent its exploitation of its poor Sp. Defence. It can however 'counter' some of its counters, with its three elemental fangs, Thunder Fang for water types, particularly Gyarados and Ice Fang for Grass-types like Tangrowth and Leafeon (though they DO have high defence, so it may not work out in the long run) as well as the Dragons and the lesser seen Fire Fang mainly for Heracross, the grass-types and the Bug/Steel-types. Stealth Rock resistance is useful and a recovery move to offset the damage that fails to kill it, as well as a high Attack stat to take advantage of Earthquake and Stone Edge, which few resist completely. With Roar and Stealth Rock also at its disposal, it can cause passive damage by team shuffling and gains fantastic coverage with its three fangs.
P.S. Somehow this is also related to that typing vs. stats topic we had a while ago.