Is this most casual way of asking out on a date?

[Anonymous]

He and I have been on two dates which went really well. Today, he asked me “wanna do something tomorrow? :)”

I said sure and asked him what he wants to do.

We both are in constant contact and share good humour, flirt too and sometimes have serious talks too. I’m just wondering if his way of asking me out was way too casual and that he might not be that serious about me. Do guys ask out this casually?

[strateguy632]

that wasn't casual but it was vague because the main thing for him was together so no specific activity. this was the better way.

[Asker]

Yeah I don’t know how I feel about this and when I asked him yesterday what he wanted to do, he didn’t reply and was talking about another things before he stopped replying. I’m not very happy about this.
We will be meeting after work and if he fishy make a concrete plan and tell me by noon or 1pm at least, I’m planning on not going.
Do you think it will be good idea to not go, considering he is bit careless?