On a side note, people citing TE3 as an IC2 replacement at all sort of shows you something, as the only real similarities are the Furnace and Pulverizer. That kind of means IC2 was only being used for Ore Processing. And frankly that's a shame, given that it's a great mod for a lot of other reasons.
Agreed. IC2 has been a staple of mine for a very long time. It's true that a lot of what it provides, is now available from other mods; but there are times when it can be exactly what you need. I'm still using a BC quarry at the moment, but I built one of the advanced ore detectors, in order to find an ideal place to put the quarry down. I also use the crop sticks to be able to grow sugarcane on farmland, which is very convenient, because it means I can grow it alongside all my other crops.
IC2's geothermal generators have been a power staple of mine since at least the retail release of Minecraft, as well. I made a tutorial (
) a year ago about how to set up geotherms, and except for the Red Power 2 stuff near the end, all of that information is still largely valid. They are simple to set up and use, and they don't change. It's good.
Some people might think that Tinker's Construct has rendered the mining drill obsolete, but the fact that TC's tools allow for an EU upgrade, means that building IC2's power armour is still worth it. You get both the tool's base durability,
and EU on top of that.
The other main thing that I've loved from IC2 since before 1.2.5, is the reinforced concrete and glass. I'm a very paranoid person when it comes to base defense, as well as making sure that I don't get lava everywhere while pumping it, so even though I've never built nuclear power, those bricks are perfect for both solid reaction chambers for other machines, and very strong, Creeper-proof base defenses.
Granted, IC2 does have a couple of minor annoyances, but it has for a very long time. The only real one is the wrench mechanic, which truthfully I've always disliked. This is mainly because my own playstyle often involves picking machines back up and putting them away when I've finished using them, rather than leaving them placed all the time. All I need to do tho is break the block, and then use NEI to get it back in the unbroken form, so it's not really a big deal. I also truthfully don't like the new hammer step in recipes, because it is fairly pointless, but again, it's not really a big deal. It would be a horrible waste of iron, but DartCraft gives me a rechargeable hammer, so that is ok.
Due to Mekanism's universal power cabling, which carries EU/MJ/UE power, and can convert between the three via Mekanism's energy cubes, there isn't really a reason not to use it, either.
IC2 has become more specialised. It is not a mod which I would build everything from, but then again, it never has been. It isn't really a "tiered" overall package any more now either, but I think is moving towards becoming an unrelated grab bag, like OpenBlocks. It's another potential solution to problems, and for me, that is always welcome.