The latest edition of the Journal of Statistical Software is out, with plenty of interesting articles for R users. A must-read is Hadley Wickham's article on "The Split-Apply-Combine Strategy for Data Analysis", which makes a compelling argument for the use of the plyr package to partition datasets and apply sub-group analyses. Also, anyone who hasn't yet purchased a copy of R in a Nutshell should check out Dirk Eddelbuettel's review: "an impressively comprehensive introduction to R". Other articles focus on the R packages tourr (for exploring multivariate data), lubridate (for date manipulation), DPpackage (for Bayesian Semi- and Nonparametric Modeling), TraMineR (for visualizing state sequences), DEoptim (for global Optimization by differential evolution), wqaim (for QTL analysis) and Rcpp (for R and C++ Integration). You can find the complete list of articles in Volume 40 at the link below.
Update 4/13: Added link to Rcpp article.