for digital IC design, if you like to take advantage of new process, you need to take care of more and more circuit issues(noise, EM/IR, timing, matching), at least on library, caches; for analog/mixed signal design, as technology keeps shrink, you need to use digital part(DSP) to help you on your analog/mix signal design, otherwise you will have nightmare if you use cmos. So you'll see more and more mixed design, and both of them, at least some concepts, will be important.