Continuous Shuffling Machines
Here's a photo of probably the most common model found in UK casinos, the Shufflemaster one-2-six (named as, you guessed it, it can accommodate from one to six decks of cards). They're usually provided by the manufacturers on a leasing arrangement and are in use across the world.
If you are curious to see what the inside looks like, there's a photo of the sorting carousel, and supporting article about the one-2-six here. I happen to agree with the author, in that there's no doubt there's a degree of latency in these devices - because of the design of the internal workings there's just no way that cards which are inserted are able to be dealt out on the next round, when it's being used in shoe mode. To what degree this latency exists is a matter of conjecture, but I would think two rounds of blackjack, possibly more. It certainly doesn't deliver a completely random shuffle, although what constitutes a "random shuffle" could be a point of debate in itself.
Can you gain an advantage from counting with CSMs?
If you believe latency exists, it means that you could keep count of the cards as they're played and raise your bets as a playing advantage presents itself - a simple case of keeping two counts (one for each of the two latent rounds of cards - if you believe it is two) and netting them off - so +8 and -2 would give a net running count of +6, giving an average of one high card per deck in play or thereabouts. You'd need a net count of +12 to gain a 0.5% advantage, but bearing in mind the reshuffle effect this would only present itself for two rounds or so, before being diluted away - you'd have to assume that the cards returned to the machine would be able to be re-dealt after the two (supposed) latent hands.
So in theory the answer's "yes", although because of the continual shuffle effect an advantage won't come up that often and then will only present itself for a couple of rounds before being shuffled away. I've never actually done this (so it remains a "theory" of mine) and have no interest in doing so, as any wins at high counts couldn't be directly attributed to something that may or may not exist.
If you find a casino where the cards are not returned to the shuffler until there are a deck or more in the discard, this would allow for any advantage to remain for longer - ie where the count continued to rise as each round was dealt out.
March 2018.