I will try to be as objective as possible in explaining why Jace is $60.(Actually it's closer to $80 now)

(1) Magic card power is usually determined by the following:

Versatility

Efficiency

(2) Prices are determined by mostly by 2 factors:

Current environment

Rarity

(2 - Current environment) You will see a card Heavily used in tourney-level constructed decks when it's versatile and efficient. When a card excel in both factors in (1), it will shape the "current environment" in (2).

(2 - Rarity) A top tier normal-rare that is currently in standard usually goes up to around $20 (see Knight of Relinquary, Noble Hierarch, and Maelstrom Pulse). A top tier Mythic-rare can easily triple that (see Baneslayer Angel).

(1) As to why [[[Jace, the Mind sculptor]]] excels in versatility and efficiency. I might not be the best person to explain it. In my experience, how a card's power-level perceived by a player is more or less affected by his or her playstyle**. What I mean is, I probably can't convince you that he's the best available Planeswalker but I can tell you that he's that good. Card advantage is always a huge game determining factor. And Jace simply gives you a lot of it. Compared to Old Jace, [[[Jace Beleren]]] gives you 3 cards from the top of your library in 3 turns and he goes away then. This new one let you look at all 3 cards the turn you play him and choose which ones to keep and he sticks around indefinitely! That single ability will make him worthwhile in almost ALL blue decks. Hence the versatility. He's also extremely efficient by netting you 1 extra cards every turn at no cost. Compared to [[[Scepter of Insight]]] which also nets you a card a turn unconditionally, the scepter costs 4 mana every card! That's how ridiculous [[[Jace, the mind sculptor]]] is...

**Like there was one time I argued that [[[Blinding Mage]]] is a more versatile, hence more useful, pick than [[[Lightning Bolt]]] in an M10 draft. The discussion was unconclusive because both are great first-pickable cards yet the other person and I have distinct playstyle.

I think he'll see play in constructed. and just the fact that he is the only planeswalker that have 4 abilities makes him more expensive..

Besides, look at his abilities; brainstorm effect for 0 counters, -1 to get 1 of the opponent's creatures out of the board.. and he costs only 4 mana to play.

It's mostly prerelease speculation that's driving the price. Now that the set's released, and people will see its true value and the price will fall according to that. To keep a price of $60, it would have to start winning games almost every time it comes into play. Also, dealers will open 100s or 1000s of boxes now that the set's released, so the price will fall. If you have a copy, sell it on Ebay right now. If not, wait a few weeks to buy your copies.

The ability to filter cards off of your opponent's library is pretty sweet. Reminds me of Thoughtpicker Witch, but in the case of Jace Mind Sculptor your opponent can get their threats back simply by cycling through or shuffling their deck.

That said, I don't disagree with your assessment. :)

[[Thoughtpicker Witch]]