Thinking about Thinking about the Kingdom

I've been wondering lately, are we thinking enough about the kingdom of God?

I've been reading through Luke (and occasionally blogging on what I read) and have been facilitating a Bible study on the kingdom, so I've got kingdom on the brain.  (Go here to read a brief description of what I mean when I'm talking about the kingdom of God.)

The kingdom is a really big deal.  In Matthew, Mark, and Luke (and even in a few curious places in John) it is the summarized content of all Jesus' teaching.  It is prominently embedded in the prayer Jesus taught us to pray (arguably reflected in the whole thing).

So how can I go for days and days and not think in terms of the kingdom?  How can I read Christian books, hear sermons, read blogs, and engage in pious conversations and not hear about the kingdom?

Why do we (I'll leave it to your imagination how I'm defining "we") seem less comfortable talking in terms of the kingdom than in terms of atonement, forgiveness, justification, and so forth?  Is it that the kingdom is harder to understand in our culture than those other concepts?  I'm not sure that it is.  Is it that we're more comfortable talking about forgiveness of sin, which focuses on faith and reckons us more passive, than about the kingdom, which focuses on repentance and has active obedience to the King as an inescapable requirement?  I'm not sure.

Here's a related thing I've been wondering: how do I announce the kingdom to the unbelievers I know?  For one thing, I need to explain the concept.  But for another, I have to get the conversation started.  What are the things that people say to which some version of "Guess what?—the kingdom is coming and is now here in Jesus!" is a coherent answer?  I think I have some answers to these questions, but I'm not satisfied with them.  I feel like there's something more that I'm missing.

Just wondering.