Here's a list of the new achievements for Ultra. I won't go in to more details yet, but most are probably quite obvious.
Perks!
Unlock all the Perks
Perk MAXED
Buy all the upgrades for a Perk
Mad MAXED
Max out all the Perks
Cash Grab
Get $10,000 in the bank
Completely Insane
Complete a 4+ minute track on Insane difficulty
Tough Guy
Complete a 4+ minute track on Suicidal difficulty
Death By A Thousand Cuts
Get 10,000 kills using Micro Missiles
Death Star
Get 10,000 kills using the Ultra Beam power up
Untouchable
Reflect 10,000 projectiles using the Reflect Shield power up
Ultra Beam of Death
In single play kill 50 enemies with 1 Ultra Beam blast
Reflection
In single play Reflect 50 projectiles with 1 Shield burst
Cool Tracks!
Listen to the Indie music in the Credits screen
Music Tour
Score at least 1,000,000 on each built in track
A Real Mine Sweeper
In single play hit 50 mines in one track without losing a life
Tug of War
Have a 10 second tug of war with a Stalker
Boss Dance
Survive with 4 bosses on the screen in Boss Rush mode
Boss King
Get to Wave 50 in Boss Rush mode
Enjoy!
Steve