Some additional details (via a forumer ofEurobricks who had access to the retail catalog) for LEGO sets based on the Marvel movies Avengers: Age of Ultron and Ant-Man, both expected in 2015:

Avengers: Age of Ultron : 5 boxes would be on the program.

Ant-Man: 3 boxes would be planned around the release of this film announced for July 22, 2015.

The Marvel range will be completed by several boxes (at least two) based on the universe of the animated series Ultimate Spider-Man.

Be warned, Eurobricks is an interesting source of information, but this forum is also frequented by guys in need of digital notoriety who are willing to say anything to get noticed. The above information should be taken with huge tweaks, one of the sources has just admitted to lying ....

Update : The references of the LEGO Marvel Super Heroes sets expected for 2015 are available on a Swiss merchant site which however does not publish the names of these boxes:

Those who follow have known for several months now that the Pirates range was likely to make a comeback in 2015.

It is now confirmed with a list of sets a priori planned for April 2015 which has just been published on Eurobricks.

We find there the set whose name was chosen during of a competition organized on ReBrick : The Brick Bounty.

As usual with the sets lists from the retailer catalog or from the computer file that LEGO sends to the various retail chains, sets exclusive to the LEGO Shop or to certain brands are not mentioned.

The LEGO catalog intended for resellers who use it to place their orders for new products is clearly available and information concerning the sets expected for early 2015 is starting (timidly) to filter through.

A forumer ofEurobricks, who was able to take a look at the preliminary visuals of these new products, distills some partial information on the DC Comics and Star Wars ranges. I uploaded a summary of what has been published regarding the DC Comics range on Brick Heroes.

An important clarification about the LEGO retailer catalog: The preliminary visuals it contains are often accompanied by minifigs which are only used to indicate the quantity of characters provided in the sets concerned. The final characters are sometimes represented by minifigs that have nothing to do with the final version that will be marketed.

Below, a recap of what we know so far about some of the sets System Star Wars expected early 2015:

75078 Imperial Troop Transport : A machine that could be similar to that of the 7667 Imperial Dropship set released in 2008 accompanied by 4 Stormtroopers.

75079 Shadow Troopers : A Battle Pack with two Shadow Troopers, two Imperial Guards in black (members of the Shadow guard imperial?) and a vehicle.

75080 AAT : The machine would be accompanied by Jar Jar Binks, another Gungan and a Battle Droid.

75081 T-16 Skyhopper : This box contains a pilot, a Tusken Raider and a [Womp] Rat which accompany the T-16 Skyhopper.

75089 Geonosis Troopers : A Battle Pack with an AT-RT and Clone Troopers apparently identical to those in the set 75035 Kashyyyk Troopers released in 2014 but with a brown / sand camouflage.

Regarding the sets based on the animated Star Wars Rebels series, the information is more than partial and very (too) vague:

75082 Tie Advanced Prototype : Three minifigs in this set including one equipped with a double-bladed lightsaber (The Inquisitor?).

75083AT-DP : A Stormtrooper (or a pilot? see here) and two imperial officers (including Agent Kallus ?)

75090 Ezra's Speeder Bike : Ezra Bridger will obviously be in this box which could also contain two Stormtroopers.

Jurassic World sets are planned for 2015 at LEGO: Chris Pratt spoke about it in an interview with the site Empire, during which he indicated that he had seen the minifig representation of the character (Owen) he will play in the film expected in June 2015. The debate then revolved around Chris Pratt's ability to differentiate between the different manufacturers construction toys, this one evoking a line of LEGO products based on the movie, but the license so far being held by Hasbro (Kre-O).

End of the suspense: A forumer ofEurobricks who had access to the reseller catalog which presents the upcoming ranges confirms that the license hitherto operated by Hasbro in its Kre-O range will be declined in 2015 by LEGO on the occasion of the release of the film with five sets.

The LEGO catalog for retailers is available and those who have had access to the visuals (mostly preliminary) it contains report many details on the sets expected for January 2015 which will be stamped "Justice League"(logo on the box).
I offer below a summary of the information available on Eurobricks.

76026 Gorilla Grodd Goes Bananas : Gorilla Grodd is a bigfig. This set contains theInvisible Jet piloted by Wonder Woman, a mech / exoskeleton for Batman, Captain Cold and Flash.

76027 Black Manta Deep Sea Strike : This box contains a Bat-Sub, a shark, another underwater craft for Black Manta, Robin and Aquaman.

76028 Darkseid Invasion : This box contains a ship which should be the Javelin of the Justice League. Superman, Cyborg and Hawkman are in this set with a pilot for the Javelin.

76040 Brainiac Attack : Brainiac, Superman, Martian Manhunter, Supergirl and a module for Brainiac identical to the one seen on the cover of the game LEGO Batman 3: Beyond Gotham.