A disclaimer: this is coming from someone who truly believes that "Playful Parenting" (ala L Cohen) is tantamount to engaging and nurturing our child's attachment to us, creating a relationship with them (Hold on to your Kids, Neufeld). Not just doing the things that we prefer to do with them, but going out of our way sometimes, even doing those things we don't particularly like which sends a strong message about how much we care. I know sometimes my DH asks me to help him with this or that and I don't really want to do it, but of course I do because he needs my help and I love him and want to be there for him. Pretend play is a very meaningful (and powerful!) way for us to be there for our children.
A game, a puzzle, these can be great fun together (we do them often

) but what I can tell you is that when I don't regularly engage in pretend play with my DS, our attachment wanes and our relationship suffers. When I do take the time however, I learn so much about where DS is at. I learn about things he's working through and in being there, playing along, I'm available to help him work through those issues. In particular, if DS and I have been out of sorts with each other (i.e., I've been distracted, busy and grumpy

), plopping down with him and following his lead is the single best way I know to reconnect and heal our relationship. It connects us in such a profound way, that no matter how difficult it is to get up for, I will keep doing it because for us, it's so very important. And usually, once I truly engage, it's easier. Sometimes it's just the getting there that's difficult. If I do my best to lose my frustration over it, I can see into the games and why they have meaning for him and how my playing along with him can help him learn, heal and move on. DS sometimes amazes me with where he takes his play. As Naomi Aldort says, "children are like little psychologists!" And I believe it because I've experienced it time and time again. Beautiful.
Sometimes if I'm mentally struggling to make the time, I tell DS that I have 20 minutes at this certain time a day and this is the time that he gets to lead me, be in charge, be the king, boss me around! Oh, how he loves this! When he gets this time with me, it pays off for him and for me. He is almost always willing to work with me on my terms when I need him too. This is the give and take of our relationship and I cherish it. By using the time limit, I can more easily initiate playtime. Often, I play longer and if at all possible, without him having to ask. DS SOOO appreciates this. It is always time well spent.
On a selfish note, I find that the amount of time I spend playing with DS in this way--when he's in charge and has my full attention--is in direct proportion to the time he's willing to spend playing on his own (i.e., he gets what he needs, the cup being filled if you will, and then is able to function happily on his own for a time).

If it helps, make a special time each day, or every other if that's better. Twenty or thirty minutes. One thing I've found that helps is to back it up to something that will help DS transition when I'm ready to move on; a meal, a program, a special activity, an outting, etc. Aside from helping me stick with it, another thing I've found about making the playtime "official" is that DS is no longer spending as much energy in trying to get me to play. He knows he can count on me for that special time, and this helps him to let go of the "obsessive need" that I unwittingly created by putting off his requests or by giving him the impression that I'm not available for that.
At the end of the day, this is really about joining DS in his world. Showing my love for him in a way that he needs me to rather than the way I'd like to. There is so much about his life and that of most children that is about joining us in our world; our homes, schedules, jobs, appointments, errands, the list goes on and on. By making time to join him in his world, it just seems well, appropriate and kind. It is entirely helpful to DS's emotional growth and well-being this parent play time. He makes this undeniably clear in a variety of ways. Not the least of which is just how connected we feel and wonderfully we communicate when he's getting that special time a regular basis.
My .02 for what it's worth.

The best,
Em