Scores and leaderboards: when you solve a level, you will obtain a score based on several metrics. This score is then visible in the leaderboards so that you can see how well you did.
Czech translations: the game is now completely localized into Czech (can be changed in the settings)
Brand new UI (no more gray buttons, towers have icons now)
Advanced tower placement mode: multiple towers can now be placed at once (activate in the settings)
Even less text in tutorials: learn by doing, not by reading
Improved lighting
Steam integrations (Steam overlay in the demo; Statistics and Achievements in the full game)