I got both versions of Black and White. I registered Black to my main Pokemon.com account while I registered my White game to a newly created account. Seeing as they were two different accounts, I have the option of getting two Eeveelutions as oppose to just one. I saved Leafeon to my main account (awesome for my Drought Doubles team), and Espeon to my secondary account (just useful in general). Reset mania will follow the very moment I get them in the Extralink of my respective games... The nature + IVs will be a horrid experience in resetting for. *shudder* It'll be well worth the effort, though.
As far as the Eeveelutions DW abailities themselves are concerned...
In my opinion, Espeon is the top pick with Magic Bounce, and it's easy to see why. It's a complete counter to Breloom, as it'll bounce back that Spore that they always like using. It bounces back entry hazards like Spikes and Stealth Rock. It bounces back status-inducing such as the aforemention Spore, as well as T-Wave, Toxic, and Will-o-Wisp. This is the definition of awesomeness. It's a shame that it can't utilize the EspyJump tactic due to lack of Baton Pass. Magic Bounce Espeon doesn't lose its usefulness in Doubles, either. Some people may even hesitate to target Espeon with a Status-catagory attack due to fears of Magic Bounce, which may work to your advtange if you don't have access to said ability.
Leafeon with Chlorophyll will see most, if not all of its use on Double Battle teams w/ Drought Ninetales. Double speed in sunlight plus Adamant nature and an ATK-booster item like Life orb or Choice Band will make Leafeon a force to be reckoned with. There's no denying this. Compared to other Chlorophyll users out there, Leafeon has the best combination of bulk and power, and its speed can only be surpassed by Jumpluff (they'll prefer Leaf Guard on Chlorophyll due to that 100 base SPD) and Whimsiscott (they'll run Prankster over Chlorophyll, any day), while only being tied with Sawsbuck, whom is brittle, but has access to Jump Kick, where-as Leafeon does not. In Single Battles, Chlorophyll isn't very useful. Between Politoad and T-Tar, getting your favorite weather effect in play via Drought Ninetales or a Sunny Day user will prove to be difficult to do, much less mantain. It's shallow movepool of minimal type coverage doesn't help things any, making switch-ins against it the easiest thing for your opponent to do via steel types like Ferothorn, Foretress, Skarmory, Metagross, etc, etc. Chlorophyll Leafeon will see most of its use in Double Battles because of this.
Vaporeon is nice at first glance, but when you keep in mind that weather effects are very commonly used the metagame, both in Singles and Doubles, Hydration is next to redundant. Water Absorb is, in my opinion, a superior alternative, as those Drizzled Surfs do nothing to Vaporeon (and we all know how much 1/2 effective, weather boosted, STAB moves can hurt), so it's an ideal switch in against Politoad, especially if you like to run it with Hidden Power Electric. Double Battles isn't much better than Singles. Then again, Water Absorb isn't particularly useful here, either, unles you like to Surf spam with another pokemon. For the sake of sparing yourself of a wated DW Eeveelution choice, great Arcues, don't choose Hydration Vaporeon.
Guts for Flareon isn't bad, considering that Flareon desperately needs some sort of power boost... Shame that it doesn't make it usable. There's better choices for Guts users. FAR better. It needs Flare Blitz to even be CONSIDERED a possibility... and even at that, it won't have Superpower due to the only accessable way to learn it is in Plat. These two things ultimately crush a Guts Flareon's dreams, which I find ironic when considering that this is a DREAM World Eeveelution.
Quick Feet for Jolteon... Is this even worth consideration? Jolteon is a speed demon as is... Why on earth would a FURTHER speed boost be needed over protection from T-Wave?
Inner Focus for Umbreon... Really? Block Fake Outs or haxing Rock Slides, but outside of that, what the point? Synchronize is superior in all sense of the word.
Glaceon with Ice Body. This one actually isn't bad on a Hail team. Combined with a Leftovers, 1/8 of its HP is restored at the end of every turn. Hell, you can make it 1/4 if you like to use Protect to stall for that extra turn of heals. The downside? It has a glaring weakness that so many pokemon have access to exploiting: fire, so Glaceon's bulk won't be particularly helpful. Warlein is superior for its type coverage and Thick Fat to turn neutral fire attack into ineffective.