Here is a factsheet from Sims Wiki that summarizes the twitter questions answered by Grant (Click on Continue Reading to view).  (Thanks to simsmx for the link)

Here’s a list of facts obtained from the Twitter session.

New Objects
  • Elevators (Sims will be able to WooHoo in them)
  • New instruments (Each with their own skill)
    • Drums, Bass, Piano
  • Shuffleboard
  • Darts
  • Bubble bar
  • New bars
  • 3 hot tubs
  • New furniture
  • Vampire inspired bed
  • Vampire altar
New interactions
  • ‘Make a move’
  • Talk and drink while sitting down
New skills
  • Drums
  • Bass
  • Piano
  • Mixology, creates new drinks, learn fancy drinks moves, moonlight as a mixologist (not a career)
  • New cooking recipes (drinks and hot wings – different drinks will add different effects)
New careers
  • Film, actor, director brances, (similar to Ambitions Doctor career)
  • ‘Teen Celebrity’ part time job, available to children of celebrities.
New CAS features
  • Breast slider for women.
  • New muscle slider for both genders (can make ribbed abs)
  • New sliders are passed down through genetics.
  • New clothes.
  • New hairstyles.
  • New facial hair (goatee and others).
  • New tattoos.
New NPCs
  • Paparazzi.
Band details
  • Bands can perform gigs
  • Invite people to join band, kick them out and hold jam sessions
Celebrity details
(not a career)
  • Acting auditions around the neighborhood.
  • Shoot B-reels for money.
  • Get money for schmoozing.
Neighborhood
  • Subways, a rabbit-hole transport system. (No loeading screens)
    • It’s free, but you can get mugged. Can be placed on residential lots as well, via buydebug.
  • New art for some old rabbit holes.
New traits

(only two new traits in Late Night)

New places to WooHoo
Music
  • New music genres.
Vampire details
  • Has thirst motive instead of hunger.
  • Can die from thirst which gives a new ghost color.
  • Plasmapacks are snacks and they’re red.
  • Bloodfruit seeds can be bought at the grocer.
  • Vampire children still go to school and must hurry when catching the bus.
  • Slightly pale an ‘unearthy’ skintone for vampires.
  • Can be cured by a potion.
  • Unique behaviors.
  • Favorite food is blood.
  • Garlic will affect them somehow.
New build tools
  • Pools on any floor.
  • Curved pools.
  • Circular pools.
  • Half-walls.
  • Shell buildings.
  • Fountain tool.
  • Moving paintings up and down on walls.

New lots:

  • Studio.
  • Subway.
  • Hidden vampire bar.
Misc
  • ‘Downtown’ is a new neighborhood.
  • New dance animations.
  • New oppertunities and wishes.
  • VIP sections have more celebrities, cooler people, better objects and activities, better drinks…overall higher quality.
  • Apartments are big “Shells” like in WA, NOT apartments like in AL.
  • You can add Downtown elements to existing neighborhoods.
  • FX machine: snow, fire, glitter, bubbles.
  • New vampire feed animations depending on relationship score.
  • Name of the Downtown district not yet decided.
  • You can form groups and romantic groups.
  • Can crash NPC parties.
  • Bouncers can be passed by bribing, sneaking in, hacking or by using your celebrity status.
  • New water reflections.
  • Late Night is rated T for Teen.
  • Twinbrook was inspired by the gulf coastline, i.e. Louisiana, Georgia, Mississippi.
  • The traffic light from the Late Night trailer is decorative.
  • ~12 new cars in FLS.
  • Possible new Trait in FLS
NOT included
  • No bowling alleys
  • No Microphone
  • No new CAS skin colors
  • No vampire coffin
  • No custom made buildings
  • No DJ Booth
  • No spiral staircase
  • No folding beds