I am using A2A at work. It's a bit like the "microservices architecture" for agents... Allows you or teams to develop agents independently and have them interact as and when they need to. No major hurdles so far.
Definitely the feature but I'm sure Gemini is seconds away (figuratively) from invading Chrome and if it has an agent mode itself, it will eat everybody's lunch in the browser space.
Quite happy when I got to play with it – but I do prefer Inngest as the code is hosted where our actual app is hosted; not on their server. So it's just easier (but it's a tradeoff).
That's basically how I use it though I cannot wait for Gemini to be a click away in my browser with the current screen/page(s)/tab(s) embedded so I can ask it stuff about the current long article/documentation page. We're becoming very, very lazy.