I just used this deck for causal plays only. The match-up against Tezzeret decks is better than the dragon-oath builds.
Tezzeret is difficult to win once Eleandra is on the table.
Dragons are better creatures against aggro-creature decks.

Glen Elendra Archmage.......... a 2/2 flier that can counter 2 non-creature spells.
Use 2 Glen Elendra Archmage in Oath/blessing........ infinity countering of non-creature spells as long as blue mana available.

2 Glen Elendra Archmage + 1 Progenitus are the creature base in this new Oath deck.

Deck list
4 Oath
2 Elendra
1 Progenitus
1 Gaea's blessing
1 Tezzeret
1 Vault
1 Key
1 gift ungiven
1 Yawgmoth's will
1 Demonic tutor
1 Vampiric tutor
1 mystical tutor
1 Imperial seal
1 Ancestral recall
1 brainstorm
1 time walk
1 Thrist for Knowledge
4 Accumulated knowledge
4 FOW
4 mana drain
4 duress
1 Hurkyl's recall
4 Forbidden Orchard
3 polluted delta
3 flooded strand
2 underground sea
1 tropical islands
2 islands
1 academy ruin
1 black lotus
5 moxen

The Tezz/vault/key combo still works in this Oath deck. Gift targets = Key/vault/Y-will/Acedemy Ruin.

I agree that it should run at 10-11 counter to improve the matchup against mono-blue.
Personally, I would add white to put 2-3 STP maindeck. Even if your 1st Oath cannot be resolved, STP help u to kill the welder, kill the ophidian, kill the tog, kill the dragon, and buy time for u to get the 2nd Oath. STP remarkably strengthen the deck.
To deal with combo, I am talking about storm and dragon. Maindeck stifle is necessary. I will put 2 stifle in maindeck and 1 at SB for cunning wish to pick.
Personally, I think intuition and AK/DA take up too many slots. I think  4 thirst for knowledge + 4 brainstorm will be good if you use the bringer/slaver lock.

Remember, a good control-combo deck should contain:
- 1) counter/disruption
- 2) the combo
- 3) draw
- 4) Answer to opponent's threat

I agree. Obviously, Oath deck become more powerful because of Forbidden Orchard. People will play test it to see the match up with other deck and time will tell whether it is really viable in T1.
Just like mindslaver last year, people discussed its playability in T1 when they first see this card. I was first tried in TnT but now it is the theme of the world champion deck this year!

The deck will be Oath, not Oathstill. Standstill poorly interact with Forbidden Orchard!

Maybe Oath will appear again because of this card.

The classic Oath with morphing, weaver, feeder is slow.

But the speed of Oath depends on what creature you are using and your build. If you use 2-3 darksteel colossus and running dragon breath, the speed can be:
- Turn 1, Forbidden Orchard, Mox sapphire, oath
- Turn 2, Oath trigger, darksteel colossus in play and dragon breath in graveyard, dragon enchanted on colossus and it swing for 11. 3 open mana for countering your opponent's spell.
- Turn 3, colossus swing again and win.

The speed is similar as Tog/Hulk and more resistant to swords to plowsheres( the 2nd colossus will come back!). The combo a little bit slower than dragon, but dragon just loss to swords/stifle.

landstill running exalted angel, it seems difficult to morph it since it needs 2 white mana.

spells:
Oath of druid x4
gaea's blessing x2
standstill x4
brainstorm x4
Nevinyrral's Disk x4
mana drain x4
Force of Will x4
Stifle x3
Funeral Pyre x3
Enlightened tutor x1

Creatures:
Darksteel Colossus x2

Mana:
Mishra's Factory x 4
Treetop village x4
tropical lsland x4
tundra x4
wasteland x4
strip mine x1
Flooded Strand x2        
Mox Emerald x1
Mox Sapphire x1
----------------------------
win conditions:
creature decks - oath
creatureless decks - manlands or oath/pyre

I have tested this deck. I had no problem in aggro decks. I can win quite well in creatureless deck, especially I can play a turn one standstill or oath.