Totally! My third liked to lay in the bassinet and look around. And, she liked to sit in the swing. What?!?! Babies really DO that?!?! I remember telling my dh, "I feel like I'm not mothering this one!" My first two had been needy just about every minute of every day, I couldn't imagine. I just assumed when I saw a baby not being held their parents must have CIO. :bag
I let my babies play some on their own, if they will, but I do like to interact as much as possible. I think it's good for them. Actually, baby #4 desperately WANTS down, and she wants to do her own thing. She's demanded to be down for a long time (4-5 months old?), and really only wants to interact with me if she needs something. Otherwise, she wants to explore. My third was more like that, too.
I will say, though, that I am working really hard to lengthen my 3rd's attention span, and I am deliberately spending more time on the floor with the happy baby to call her attention to things and to encourage her to focus for longer periods of time. There's just so much going on that their little minds flit from one thing to the next and, I feel, they need help learning to pay attention. Mostly, I think they are just trying to keep up with the others. I know that's not exactly what your question was about, but I wanted to throw it out there.