Guess I'll have to ask Apple Store folk to be sure that no (recently discovered?) badness occurs re LIon or Mtn. Lion upgrade--and get reassured that my WD-'Studio' (tiny, shiny 2.5" box) Time Machine drive shall know what to do with its older records, at Lion install ... as it did, nicely 'twixt L. and Snow L.)

PITA for the d/l, on my crippled 400K Comcast BW. Maybe Store will sell me a CD of the sucker; would hate to have to schlep Klaatu / find place to park / waste half a day.
Will check out AS's linkie next..

Thanks for an encouraging 'compatibility' :-)