A bit scary. However as they pop up (slowly) every ten days to transmit that reduces the chance of a hit greatly. And the design looks like it would be pushed aside readily - I'd rather hit that than a log. There is nothing on the site about collision assessment which makes one wonder if they thought about yachts, but of course we all want better weather data!
I worked with John Swallow and his neutral buoyancy floats off the Alaskan coast in 1957. Nice to see that the concept has matured into something bigger!