Board Thread:Questions and Answers/@comment-8499212-20130505212250/@comment-1661144-20130507151237

I don't know, I did some looking around on the tekkit site, and found this

"We're most interested in delivering a solid experience. Can't make it a popularity contest and stubbornly stick with the celebs just because they're well known. IC2 and Redpower were both cornerstone mods but new modders have stepped up to produce some amazing work. We've always been about highlighting the amazing work of modders and showing them off to the community. With the new mod lineup for Tekkit, we see a lot of those modders who are easily going to become the next big recognized names. Most of their mods replace a lot of the IC2 and Redpower functionality with their own takes, which in many ways are a bit more cutting edge and easier on computer performance. Take that with the fact that Redpower has always been the major holdup for every pack update adding weeks onto release dates. We think it's just time to move on. Just have to grit our teeth and weather the initial knee jerk reactions until people realize that these new mods are on a whole new level, and this update is probably going to be the best in a long time."

so yeah... thermalexpansion is the new industrialcraft i guess