Traditional emerging markets, as measured by the BRICs, lagged in 2012 compared to the new generation of emerging markets and developed markets (SPY). The MIST index was basically created to differentiate these emerging countries, for some have better investment profiles than others. For example, the M in MIST (Mexico) has a lower unemployment rate than the USA. Moreover, Indonesia, I in MIST, has lower credit default swap rates on their 5 year bond compared to China; the C in BRICs.
In the age of the ETF, it is easy to build a diversified emerging markets portfolio. The MIST index below was build by taking the average of EWW, IDX, EWY, and TUR.
MIST=Blue
BRIC=purple
SPY=red/green