FEATURES
********

  o provide a [<-.zoo method that is fully consistent with [.zoo
    so that the following works:
      a <- zoo(matrix(1:10,5,2), 2001:2005)
      a[I(2003), 2] <- NA
    (Note: as in window<-.zoo)

  o rollmean returns all NAs when na.pad = TRUE

  o allow plot.zoo to accept a list of zoo objects -- this would
    be particularly useful in the case of line plots of multiple series
    with different time bases since NAs are introduced by merging 
    and they can cause the drawn lines to be undesirably broken.
    (Current workaround is to use na.approx.)

  o incorporate runmean in package caMassClass
 
  o allow log to be specified per plot in plot.zoo
  
  o performance enhancement when using arithmetic on zoo objects. Check
    if they have same index first.

  o speedup for indexing strictly regular series. Test with is.regular first.
	set.seed(1)

	x <- ts(rnorm(5000))
	xz <- as.zoo(x)
	system.time({  ################################
	  for(i in 1:5000) if (is.regular(x)) 
		x[(i - tsp(x)[1])*frequency(x) + 1] <- 0
	else
		window(xz, start = i, end = i) <- 0
	},
	gc = TRUE)
	system.time( for (i in 1:5000) xz[I(i)] <- 0, gc = TRUE )
	system.time( for (i in 1:5000) window(xz, start=i, end=i) <- 0, 
		gc = TRUE 

  o zoo()
    - support zoo data.frame objects (and zoo list objects)
    - fully support zoo factor objects [limited support already 
      available]
    - idea: new class "Zoo" that is not a matrix plus attribute
            but a list with slots "coredata", "index" and "frequency". 
    
  o merge()
    - names not processed correctly when retclass = "list"

        
  o misc functions
    - interface to additional statistical routines such as the ones
      referenced in:
      http://CRAN.R-project.org/doc/contrib/Ricci-refcard-ts.pdf
      [Z: with as.ts.zoo() most of the functions work directly
       by coercing the first argument to "ts"]


  o QA
    - regression test suite
    - additional use and testing



INTERFACES
**********

  o provide fCalendar interface routine to the Rmetrics projects



DOCUMENTATION & COMMUNICATION
*****************************

  o R news article based on the vignette

  o some data to include with zoo

  o more examples for the help files

  o FAQ
