Competition in an emerging market is good, though this seems to be competing in the hardware area only. The price may soon be down to the point that we can pick up a device with Echo-like functionality at Walgreens or CVS!
But there's still a question as to which assistant platform to back. As it is, the market for "intelligent" voice assistants already seems fragmented with multiple platforms. Siri, Google Now, Alexa, and Cortana are the big players, but they're not the first nor the only ones. There are also countless others such as Vlingo, BlackBerry Assistant (which appears to be aborted and left to die with BB10 already), Hound, Braina, SILVIA, Nina... some of which have limited utility, but the list goes on.
Just a few years ago, we also had other smartphone OSes competing with the major players. There was Palm/HP's WebOS, Palm OS, Nokia's Symbian, BlackBerry Classic (OS 7 and earlier), BB10, Samsung's BADA, Motorola's iDEN, and some others I never had exposure to. Despite having some unique strengths, these have faded away while the strongest platforms survived. It appears that we're going through the same fragmented growing stage for voice assistants now. I expect that setting up a business model around any of them is still a little of a gamble at this point. However, as the current smartphone platform leaders, Apple and Google seem to both have a significant advantage over Alexa, Cortana, and others by making their assistants exclusive to their smartphone platform. They didn't have that advantage the last time around.