Last November, the NASDAQ Composite (INDEXNASDAQ:.IXIC) crossed the 4000 mark for the first time since the dot-com crash, when it topped out at 5049 in March 2000. While investors are feeling bullish right now, and there have been a few tech IPOs that seem pretty optimistic, the makeup of the NASDAQ CM has changed dramatically over the years. It now has a smaller IT bias, fewer companies with larger market caps, and valuations that signal the growth-heavy nature of NASDAQ listed companies without having left orbit. NASDAQ has half as many listings, but larger market caps The most obvious difference between…