I bought it on release day and read the rules. It actually seems like a well thought out ruleset to me. It has taken the best elements from Kill Team and 40k, streamlined the rules, and balanced the units a little better, so that there aren't as many auto-shelf/auto-field units. In other words, it seems like units that you normally would leave home (because they just suck sooo bad) in a game of 40k you could bring in an apocalypse game and be useful, and in some cases really useful.
The alternating activations of detachments seems like a good balance between UgoIgo and alternating units. It would keep both players engaged and speed up the game, especially with the orders being the same for the whole detachment. Combat seems easy and self-explanatory, saving time on the barrels of dice rolled. Damage at the end of the round is probably my favorite part. Models that might otherwise be a liability in 40k have at least one turn to be useful in apoc, and make it so you don't feel bad for bringing it because (for the most part) it won't get wiped from the board before you get a chance to use it. While I understand Alpha-Strike was a big part of 7th edition (still prevalent in 8th, though diminished somewhat), and that it is a common strategy (especially in the competitive realm of the game), it can be disheartening to have half your army wiped out by a first turn opponent before you even get to use the models you brought. I've been on both sides of alpha strike, and it isn't fun for either player (of course YMMV). The image of armies launching salvos and barrages of fire at each other across the battlefield is better visualized with the apocalypse ruleset.
I also see that the strategy of the game changes apoc. Instead of positioning your entire army, it becomes more of a back and forth chess game of which detachment moves first, which ones you want to set up to counter strike if the opponent moves a certain detachment, etc.
I've also observed in the ruleset that while it still allows for soup (especially at the scale of the game), it also encourages monofaction lists to some degree better than 40k. And the building rules are soooo much clearer and simpler. The cards seem to be more for adding flavor of the army in contrast to the simplification of the units in the ruleset. While some cards may be more powerful than others, they're still one use, and again, damage doesn't happen until the end.
I've read several opinions that assume GW might be using Apocalypse as a testing ground for 9th edition (or an 8th errata). That might mean that this is the direction in which GW will take the game. Either way, there seem to be vastly more positive opinions of the game than negative.