[R] different outcomes using read.table vs read.csv

[jatwood]

Good Afternoon
I have noticed results similar to the following several times as I 
have used R over the past several years.
My .csv file has a header row and 3073 rows of data.

 > rskreg<-read.table('D:/data/riskregions.csv',header=T,sep=",")
 > dim(rskreg)
[1] 2722   13
 > rskreg<-read.csv('D:/data/riskregions.csv',header=T)
 > dim(rskreg)
[1] 3073   13
 >

Does someone know what could be causing the read.table and read.csv 
functions to give different results on some occasions?  The 
riskregions.csv file was generated with and saved from MS.Excel.

Joe A