I have not played either, however there is a thread on RPG.net that discusses many of the same things: The RPG.NET thread on the topic
I've quoted some relevant parts below:
"Troubleshooters is the 25th Anniversary edition of the Mongoose 2004
PARANOIA rulebook (formerly known as XP). There are minor tweaks to
the rules, but it is basically the same game. Likewise, the companion
Internal Security rulebook uses the same system, though there is
extensive new material there for BLUE-Clearance IntSec missions.
Neither is mechanically complex, and both place unique emphasis on the
Gamemaster's supremacy. Every rule in both books exists as a
non-mandatory advisory to the GM's incontrovertible authority.
[...]
Troubleshooters, in particular, adapts the XP GM Screen's "mission
blender," a collection of tables that lets you generate an entire
mission randomly with the roll of a mere five dozen or so d20s.
Troubleshooters also includes Ken Rolston's classic introductory
PARANOIA mission "Robot Imana-665-C" as well as a fine new mission by
Gareth Hanrahan, "The Quantum Traitor."
---Allen Varney, 04-16-2010
"If you have Paranoia XP, you can play Paranoia: Troubleshooters - the
mechanics and content are 90% identical. The only substantial
difference is that Troubleshooters returns to the old Treason Point
system, with the more complex "Treason Damage" mechanics reserved for
Straight games.
[...]
As for rules for mission structure, Troubleshooters is pretty much the
same as XP, apart from some expanded GM advice and some fun tables for
randomly mission generation (which sometimes even produce sensible
results). "
---David J Prokopetz
Other comments made in the thread indicate that the official development blog has many insights into the changes.