Differences between ed 1 and current ed

[Juankis]

Off the top of my head:
- The education tables are more in line with the setting, gone are the days when 1 in 4 characters had ninja training.
- More options to mutate your character, with extra powers and more natural weapon varieties.
- Thowbacks, Purebreeds and Chimeras, for some wild mutant fun.
- Vestigial traits you can use to increase your BIO-E pool.
- Expanded anymal psychic power selection.

Other than that, the book is the same as the orginal ATB sourcebook, with all the animals and gameplay rules thrown in. I might be missing somthing else, but the room with all the RPG books is under constat flux, so finding anything in there requires a full archeological expedition.

[Fubarius]

Off the top of my head:
- The education tables are more in line with the setting, gone are the days when 1 in 4 characters had ninja training.
- More options to mutate your character, with extra powers and more natural weapon varieties.
- Thowbacks, Purebreeds and Chimeras, for some wild mutant fun.
- Vestigial traits you can use to increase your BIO-E pool.
- Expanded anymal psychic power selection.

Other than that, the book is the same as the orginal ATB sourcebook, with all the animals and gameplay rules thrown in. I might be missing somthing else, but the room with all the RPG books is under constat flux, so finding anything in there requires a full archeological expedition.

To further clarify.
The education system is rather new. You have a background similar to the old system, and most backgrounds then pick an apprenticeship. The old school "skills learned from on the job training with an experianced Master" type of apprenticeships. So a weaponsmith from the Elite Millitia will be a drastically different character than a weaponsmith from a Boarderland background.
Some of the new animal abilities do tend to up the power level a little, especially crushing strength (similar to supernatural strength in Rifts).
Purebreeds are societies of mutant animals where the mutations of stabilized, so all have very similar size level, mutations, and special abilities. Often they'll have very little room for customization, though if you wanted to build that same character as a normal mutant you'd need more Bio-e than normally available.
The vestigial traits can be used to add A LOT of Bio-e if you twink out a bit. A size level 20 mutant elephant with full hands, biped, and crushing strength is deffinatly doable. Again power level seems to have gone up a bit. No longer will most of your characters be 4" tall (as all my old system characters seemed to end up). You can also use the following to gain even more Bio-e for your extra large characters, big and slow (5 bio-e for a penalty to SPD and PP), really big and slow (10 bio-e for a larger penalty), big and dumb (5 bio-e for a penalty to ME and IQ), really big and dumb, and by combining the two.
The expanded psionic table is really more of a compilation of different psionics from different old system books.