NEI Integration is two things-- a playground to try out new types of Not Enough Items recipe handlers, and a place to put NEI handlers if I somehow can't get them into the mods they were made for. The mod aims to stimulate other mod developers to add NEI handlers to their own mods, and to help them make their own handlers easier by providing examples.
This is a list of the NEI handlers that are in the mod.
Minecraft Forge (disabled by default)
List of all registered Fluids and associated Fluid Containers
Ore Dictionary usage handler
Cyanite Reprocessor recipes
Compressor, Macerator, Magnetizer and Plate Machine recipes
Recipes of all of the processing machines and the mod's custom shaped crafting recipes
Recipes of most machines that produce or consume fluids, and the Laser Drill (including which foci works on which ore)
Presser and Apiary recipes
Blast Furnace, Coke Oven, Rock Crusher and Rolling Machine recipes
NEI Integration includes some other features that can be useful to developers. Normal players may also like them, though.
Item tooltips (can be toggled and configured in the config file or Forge's config GUI)
Ore Dictionary names, Item IDs (like 'minecraft:stone'), Fluid Container information, and burn time in furnaces
Additional data dump types for NEI
Loaded mods, registered Entities and Tile Entities, dimensions, Ore Dictionary Entries, chest loot, registered Fluids and related Fluid Containers, and NEI recipe handler class names