I was very excited to see the Eeveelutions return so soon in this set. Sadly, after readin the translations, it seems that only some of them will actually see some play.
Jolteon - Thankfully, I'm glad to see that they gave Jolteon straight forward attacks this time rather than its usual catch of having to discard an energy or two to unleash its full potential. A solid 70 damage for 3 energies will easily KO most pokemon weak to it, so it's a decent match up against a water deck, especially with Rain Dance becoming popular again. Agility? For one energy and 20 damage? Not bad for early game.
Vaporeon - This kinda dissappointed me. Am I the only one that thinks that this is practically a waste of an Eevee? Three energy for 30 damage to two pokemon? Even for a spread deck, isn't that overpriced? Then again, Rain Dance somewhat makes up for this if run in said deck. I hope Glaceon brings a better name to the "water-lutions" when it comes out. Meh. At least it's not restricted to Benched Pokemon. It can still hit the active... but just for 30.
Flareon - I think the only play this card will see is in a Eeveelution deck. At least it's handy against grass decks. I'm not fond of the fact that you have to discard a fire energy for its strongest move, Flamethrower, but then again, 3 energy for 90 damage ain't too shabby, either. There are better fire types out there, though, so this will likely be Eveelution-deck exclusive.
Espeon - I personally like this card. May give spread deck a hard time since, for one energy, you remove 4 damage counters from ANY of your pokemon (not just one) and "snipe" one of your opponent's pokemon for the same amount.
Umbreon - I look forward to seeing/using this card. The first attack explains it all. With powers and bodies still widely used on most attackers, I think this card will see somewhat common play as a teck against such pokemon.
Eevee - One word. Lame. I'll go with the Call for Family one from the Metagross vs Leafeon Expert Deck.
Overall - Considering the number of doorways for a number of good decks opening up, this round of Eeveelutions leaves me hungry for a lot more. The Eeveelution have a number of hurdles to overcome if they wish to become a good deck for the HS SS era. For one, they sadly lack the consistent strong attacks to to make an Eeveelution deck able to effectively take advantage of weaknesses. Jolteon and Flareon were the only ones that met the criteria, and aside from sharing Eevee as their basic form, there's absolutely zero synergy between them. Nothing supports each other. Secondly, energy acceleration is currently improssible for these Eeveelutions. The ones with 3-energy attacks (Jolteon, Flareon, and Vaporeon) all require two specific energy types, so that therefore makes Double Colorless energy utterly useless. Rain Dance only works with Vaporeon, so unless a playable attacking Glaceon comes out (Glaceon for main attacking and Vaporeon for picking off pokemon on the bench as needed), Dance-lutions just won't be seen playable in the HS SS era. Unless energy acceleration improves (scream Double Rainbow Energy plz?), a reliable Eeveelution deck draw engine comes out (like Delcatty from Power Keepers at the least?), or Eeveelutions get remade yet again, it would seem that this era of Eeveelutions only presents Leaf-rade (Leafeon + Roserade) and possibly Dance-lutions (Rain Dance + Glaceon + Vaporeon) as possible playable decks while Espeon and Umbreon will serve as random additions for different deck variants. Glaceon, there's a great deal riding on your release. PLEASE don't dissappoint us.