Lower level minions giving more xp..
If this applies to higher level minions as well then I see yet another farm fad coming.
Don't count your weasels before they pop dink!
Its an old bug but level 1s give 2x xp.
H: Blaster 50, Defender 50, Tank 50, Scrapper 50, Controller 50, PB 50, WS 50
V: Brute 50, Corruptor 50, MM 50, Dominator 50, Stalker 50, AW 50, AS 50
Top 4: Controller, Brute, Scrapper, Corruptor
Bottom 4: (Peacebringer) way below everything else, Mastermind, Dominator, Blaster
CoH in WQHD

I just tested this at levels 46/47/48/49/50 on a level 50+1. There were no anomalies in XP earned, though there was some variation due to enemies taking damage from other sources (such as falling damage).
It only applies to level 1 mobs. If your character is in the 1-5 range you will get 2x for beating on level 1s.
Roll a new character, beat on level 1 mobs, check out xp, beat on level 2 mobs check out xp. Level 1s will give more than level 2s. I've been letting the people in charge know about this bug for awhile now.
So if you are fresh out of outbreak (meaning you are level 2). level 1s should be 8, but they give 16. Level 2s will give 10.
H: Blaster 50, Defender 50, Tank 50, Scrapper 50, Controller 50, PB 50, WS 50
V: Brute 50, Corruptor 50, MM 50, Dominator 50, Stalker 50, AW 50, AS 50
Top 4: Controller, Brute, Scrapper, Corruptor
Bottom 4: (Peacebringer) way below everything else, Mastermind, Dominator, Blaster
CoH in WQHD

I have altitis and I noticed today while trying out a new blaster, level 4 at the time, that minions (Hellions to be exact), that conned 3 levels less than my blaster gave 2 more xp, than ones that conned 2 levels less, and ones that were one level less gave as much xp as ones that were 2 levels less...
ie. Level 4 Blaster, defeats level 1 Hellion 8xp...Defeating level 2 Hellion 6xp...defeating level 3 hellion 8xp.
Just a weird thing I noticed
"...well I have wrestled with reality for thirty-five years, Doctor and I am happy to state I finally won out over it." Elwood P Dowd (from the movie Harvey)