A special double edition of the Package Update Roundup this month! This is a list of new or updated packages that were released for R in December and January, as announced on the r-packages mailing list. To include other updates on this list, please email David Smith. For a complete list of all updates on CRAN, see the CRANberries archive for December 2009 and January 2010. Follow package name links for ratings and other information on crantastic.org.

dcemriS4, a package for medical image analysis, has been released to update package dcemri.

Deducer, a cross-platform data analysis GUI, has been updated.

doMPI, a backend for the foreach package for parallel computing, has been updated. 

exact2x2, a package for exact conditional tests and confidence Intervals for 2×2 tables, was updated to allow optionally give an exact McNemar’s test together with odds ratio estimates and confidence intervals.

exactci, a new package that calculates exact tests and confidence intervals for binomial and Poisson tests, has been released.

ff and bit, two packages that help manage large datasets in R by mapping them to disk instead of storing them in memory, have been updated.

fortunes, a package delivering snippets of amusing R wisdom, has been updated (and now includes more than 250 fortunes!)

GGally, a package to draw plot matrices (like pairs does, but using ggplot2), was released.

ggplot2, the comprehensive high-level graphics system for R, has been updated adding several new features.

itertools, a new package of tools for manipulating iterators, has been released. 

mecdf, a package for multivariate ECDF based models, has been released.

micEcon, micEconAids, and miscTools, three packages for microeconomic analysis and microeconomic modelling have been released (these packages were previously combined into a single micEcon package)

mspath, a new package to fit multi-state path-dependent models in discrete time, has been released.

parcor, a new package of tools to estimate the matrix of partial correlations based on different regularized regression methods, has been released.

pgfSweave, a package that improves the process of including graphs in Sweave documents, has been released.

randomSurvivalForest, a package for ensemble survival analysis based on a random forest of trees, has been updated with new model controls.

randtoolbox, a package for random number generation and testing, has been updated with new features.

RobASt, a family of packages for robust asymptotic statistics, has been updated.

Rcpp, the package interfacing R with C++, has been updated to make integration between R and C++ even easier.

sp, a package that  provides class definitions for spatial data, and utilities for spatial data handling and manipulation, has been updated to improve performance.

sqldf, a package for accessing data in data frames using SQL, has been updated.