Possible additional developments in no particular order:
---------------------------------------------------------

 [done?] options to handle quantiles in rounded continuous data like SUDAAN
   does (if I can work out what it does).

 - Score-based confidence intervals for glms

 - Rao-Scott-type tests for glms.

 [done] More general HT estimator for sampling without replacement
 	- using joint inclusion probabilities
	- using population first-order inclusion probabilities and Hartley-Rao approximation
	- using Overton's approximation and sample inclusion probabilities
        [done] using Berger's approximation and sample inclusion probabilities.

 - GEE. 

 - Parametric survival models (you can do these with svymle)

 - linear mixed models?

 [done] standard errors for survival curves, particularly in two-phase studies

 - an interface to twophase and calibrate for IPTW estimation.

 - Replicate weights for two-phase designs and for multistage designs
   with large sampling fraction (Fukuoka's BBE)

 - parallel processing for replicate weights, svyby(), svyrecvar()?

 - Gini index and other summaries of concentration and inequality.

 - Krista Giles' respondent-driven sampling estimators
