Music Trends: Drum Machines by Decade.

Are the 2000s the era of the Roland CR-78, 68, XXXX....

I don't recall the CR sound ever being as popular as it is at the moment. - those pithy hats, snares, 'toms' etc seem to be around a lot more these days, perhaps due to the popularisation by DFA, Beardo Disco resurgence..etc, than they ever were in the 90s at least.

Are there trends in drum machine use and what do they say about music?
what were the Drum machines du jour of the past few decades?

there is a great thread on 80s drum machines on vintagesynth.com but it turns a bit messy. the general consensus for the 80s was all of the Linns, the Fairlight, and samplers. 808 and 909 were definitely present, even ubiquitous in house/techno in the 80s but perhaps their golden decade is the 90s?

Well, the TR-909 springs to mind. It was THE machine of the early to mid 1990s (having flopped at its original release in the early 1980s) but is currently out of fashion again. Conversely the Linndrum - people would have laughed at you if you suggested using it in 1993, but it's now back in fashion.