Version 6.0 added a collection of carefully optimized functions to Mathematica's powerful arsenal of numerical handling capabilities.

New List-Manipulation Functions

Span (;;) — conveniently pick out sequences and sub-blocks from data

Accumulate  ▪  Differences  ▪  Tally  ▪  Riffle  ▪  ArrayFlatten

New List Analysis Functions

BinCounts, BinLists — count, list elements in particular collections or ranges

New Data-Handling Functions

MovingAverage  ▪  MovingMedian  ▪  ExponentialMovingAverage  ▪  LeastSquares

FindFit (modified) — now supports constrained nonlinear fitting

FourierDCT, FourierDST — discrete Fourier transforms

New Built-in Statistics Functions »

Commonest  ▪  MeanDeviation  ▪  Skewness  ▪  Kurtosis  ▪  ...

New Exploratory Data Analysis

FindClusters  ▪  Nearest  ▪  NearestFunction  ▪  EuclideanDistance  ▪  ...