Possibly derailing the topic here, but anyways;
I was reading through 'The Hobbit' again and I noticed how Tolkien himself refers to orcs in the book. According to him, basically, goblins, hobgoblins and orcs are interchangable, but usually used (in that order) to give quick reference to the size of the goblins.
i.e. Goblins were the smallest, maybe 4-5 feet, hobgoblins were around humanoid size, maybe 6-7 feet tall, and the bigger ones would be referred to as Orcs, probably 8+ feet.
T'was interesting to me
I also did some reading, after I read here that the reason DF goblins are immortal is because they are Tolkien's goblins and not DnD goblins. Tolkien's goblins are corrupted elves, and therefore also immortal. One of the places I looked on the Internet said that Tolkien realized later that hobgoblins were the smallest rather than goblins, but since he had already written them as being the opposite that he left them that way.
Gary Gygax's bugbears are described a large, hairy goblins.
Apparently, the only civilized races my modded DF that did not derive from elves were dwarves, humans, kobolds, and frost giants. Everything else was varying sizes of goblins, so I stopped playing while I thought over whether I needed four flavors of goblin in my game.
After a couple of days I decided to go ahead and keep them, but I made hobgoblins one size smaller than goblins and gave hobgoblins finite lifespans with litters and faster maturing young. I figured goblins were the original corrupted elves and so were a little smaller but still immortal, as is true vanilla DF. I made orcs the same size as elves and left them as immortal, as being superior examples of the original goblin type. I made bugbears one size larger than elves, with a finite lifespan and litters, but left the maturation age as 12.
While I was editing things, I made frost giants giant-sized, doubled their maturation age, and removed them from their horses. Things of size 12 should not be able to ride horses.
I made them all babysnatchers so I could add the intelligent tag and still have them not come with caravans. I find it quite amusing to look in legends mode and see the orcs kidnapping from each other as well as from all the other races.
I kind of wonder why DnD needs Dark Elves when it's got all those corrupted-elf goblin types already available, but I suppose they had to circumvent Tolkien's copyright claims as they did with hobbits. Since Tolkien drew his material from folklore, I'm not sure how much can really be claimed, but that's not my problem.