1990 was so much better than 2010, it's ridiculous.
Smart phones (or any cell phones)? Meh. Somehow I was able to get a hold of whoever I needed to at any given time back then.
Internet? Meh. Seriously, would your life actually end if you couldn't update Facebook or post on ATOT? Get a life! </Shatner>
I honestly can't think of anything totally mind-blowing or revolutionary from the last 20 years. (Like time travel, cold fusion, Mars bases etc)
I'd probably be most disappointed by the nearly complete lack of a manned space program by the US. Totally lame.