Don't think anybody mentioned Karakas as another possible answer to this guy.

Another try at this concept:

Knowledge Reflection
 
Instant
Until end of turn, whenever a player would draw a card, each of his or her opponents draws a card instead.  This effect does not apply to the first card drawn by a player during the draw phase.

The enchantment version suffers from a few things:

1.  Once in play, nobody would play into it.
2.  Has dangerous brokenness potential when combined with other cards.
3.  Doesn't stop Ancestral Recall.

This new version fixes those things.  The symmetry is still required to prevent a combo with Timetwister/Wheel of Fortune.

Note that #1 and #3 apply to Chains of Mephistopheles as well.  So an instant-version of that could work too.

Something that is worth noting is that while this effect is killer against Ancestral Recall, it is even more killer against Brainstorm!

Thanks for the feedback, Mr. Fantastic.  

I was aware of the priority issues with Demonic Tutor as you describe - I guess I'm banking on the fact that players sometimes don't cast their Demonic Tutor target immediately for this card to have its desired effect.  And even if they do cast their DT target immediately, resolving the trap might still be crippling.

I don't expect my first attempts at card-drawing/tutoring hate to work, but I'm hoping the arguments I made in the other thread inspire others to come up with some better alternatives, and that these ideas will eventually reach folks at WotC.  

The way I see it, the Time Vault combo only works in a BU-based deck, because you need cards that allow you to hunt through your library for the combo pieces.  Given that such cards are too powerful to begin with and arguably distastefully homogenize much of the vintage metagame, I feel a good way to answer Time Vault is to print cards that hate on the card-drawing and tutoring mechanics, to the same extent that Leyline of the Void and Planar Void hate on dredge.

The only such usable hate cards I can think of that do this currently are Chains of Mephistopheles (card-drawing hate) and Aven Mindcensor (tutoring hate).  There is room for much more creative alternatives.

I think the printing of such cards will help answer the Time Vault (read:  black-blue) problem.  It won't make the strategy go extinct, just like no amount of Ichorid-hate has made the Ichorid deck go extinct.  But forcing card-drawing/tutoring based decks to run anti-hate will make them more fragile and thus diversify the metagame.

While modifying the B/R list or adding errata can have violent, unforeseeable consequences, printing slightly better versions of Chains of Mephistopheles and Aven Mindcensor should allow for a more careful, controlled shift of the metagame with minimal disruption to the secondary market.

Finally, since hating on card-drawing and tutoring has a theme of nature and justice, it would most likely belong in green or white - colors which could use greater relevance in the vintage metagame.

I've posted some examples of what such hate cards might look like in separate threads:

http://www.themanadrain.com/index.php?topic=39560.0
http://www.themanadrain.com/index.php?topic=39555.0

What are some examples of reusable bounce?  Anything that would be easier to pull off than a combo with Necropotence?

Why?  Doesn't seem as interesting to me then.  I don't think there are any power level issues as is.  You have a card advantage of +2 on your opponent's turn and a card advantage of 0 on your turns.  On average, then, it's equivalent to a WW cantrip.

There might be broken interactions with other cards, but I can't think of anything too wild.

Guarding of the Grave

Instant
Split second (As long as this spell is on the stack, players can’t play spells or activated abilities that aren’t mana abilities.)
Flashback (You may play this card from your graveyard for its flashback cost. Then remove it from the game.)
Target player sacrifices 2 life for each spell he or she cast from his or her graveyard this turn.

I feel like flashback and split second are needed to combat Yawgmoth's Will -> Duress or Yawgmoth's Will -> Force of Will.

Scholars' Exchange
 
Enchantment
Whenever a player would draw a card, each of his or her opponents draws a card instead.

This card would neuter vintage staples like Brainstorm, Ponder, Thirst for Knowledge, Bazaar of Baghdad.  As a bonus, an active Vault/Key no longer becomes an auto-win:  you must either be able to win with your current board/hand position, or you must risk a gambit of attempting to deck your opponent before he draws into an answer.  The extent of that risk could be greater if the appropriate tech is used.

Decks like Tez or TPS rely on the mechanic of tutoring (Demonic/Vampiric/Mystical Tutor, Tez, Tinker, others).  I think it would be interesting to print cards that specifically hate on this mechanic, more so than Aven Mindcensor does.

Soul Scourge Trap
 
Instant -- Trap
If an opponent cast a spell and searched his or her library this turn, you may pay rather than pay Soul Scourge Trap's mana cost.
Search target opponent's hand and library and exile one card from each.  The opponent shuffles his or her library.  Draw a card.

Exiling from both hand and library ensures that you nail both Demonic Tutor and Vampiric/Mystical Tutor.  The "cast a spell" clause is to mitigate the usability of the card against fetchlands.

This is my first post, and I'm just a casual player, so please don't bite. 

I was playing on MWS with a UWG Noble Fish deck (Selkie, Meddling Mage, Heirarch, Qasali, Tarmogoyf, Null Rod, counterspells, wastes).  My opponent played something like a mox and a Sensei's Divining Top early.  I figured I was most likely up against Tez/tendrils/oath. 

Anyhow, it was my turn, and I decided to play Meddling Mage naming Sensei's Divining Top.  I must have not had other good options, but I wonder if it's better to just wait out a turn or two to gain more information about my opponent's deck before casting the Mage.  Maybe Mage doesn't deserve a maindeck spot precisely because of this sort of quandary?

Sorry I don't remember too many more details, besides the fact that I was eventually done in by a Yawg Will into Tendrils.