Old LFR Loot System - You were not only at the mercy of the bosses dropping one of 4 items that you COULD use (RNG #1), but also about rolling higher than EVERYONE ELSE that could use it (RNG #2), cause no matter how many of you say "Oh, I passed on gear I didn't need", we are a bleeding minority that is so small in that respect it isn't funny. The most winners of any run of either half of Dragon Soul was 16 (4 bosses per half, 4 items per boss).
New LFR Loot System - You are at the mercy of the loot RNG of getting something your spec can use, based on that boss' loot tables. And every boss has at least ONE item for every class and spec. Not always the best item, but it is there. No matter how many people win loot, you always got the same chance of winning. Most people that can win an item per half of an LFR queue is up to 150 (75 for normal rolls, 75 for bonus rolls), though the odds of THAT are beyond insane.
I'll take the new system any day. When you remove the "other people" from the equation of who gets loot, it becomes a better system. I mean, this week, on Wednesday, myself and 6 guildies joined up to do both halves of HoF. We one-shot every boss (this included the second half, as a first-time run for virtually everyone in the LFR group), and I myself got a total of 4 items and 2 sigils of wisdom for the runs (Ret Paladin). Both times I got equipment, it was 2 items from 1 boss: Got the Ring on Blade Lord, bonus rolled the Belt. Got the Leg Token on Amber-Shaper, bonus rolled the Shoulders. At the very least, our whole guild that was present each got at least 1 item drop that night. With the old LFR, that wouldn't even be anywhere near possible.