What is happening
I've pretty much finished the garrisoning update - in the new build, which I'm about to release in a couple of days, both your units and the enemy will be able to use the houses for shelter and ambushes.
Before I release it, however, I still need to do a lot more testing - it's gonna take me a couple of days, so I don't have the specific release date, yet.
Why it took so long?
The previous versions of the game had no concept of targetting buildings, or shooting out of them. The only valid targets used to be the game "actors" - cars and people, and changing this was a rather complicated process. Actors generally only do one thing at once - either they are engaged, or are doing anything else. For the buildings - you can have both civilians and enemies inside, with player units trying to breach at the same time, and other units shooting at them. In other words - it's not as easy to develop.
So when do you release it?
This week. But I don't know the exact day, yet - I'm still testing.
What will you work on next?
Due to popular demand, the next update will be the game saves. I have a lot of updates planned for the gameplay itself, but people are invariably disappointed when they realize the saves don't yet work in the game, and this is the feedback I get the most often. So, here we go - once the garrisoning is out, I'm beginning work on the saves.