In my experience, most people have found it takes longer to get the extension than it does the flexion. On the opposite side of things, as usual for my crazy body which does everything backwards, I have good extension, but not the best flexion. I tell you this to point out how everyone is different, and our bodies/knees recover at different rates.
What I have found to be exactly the same with every single recovery is the need for a ton of patience. This is a long recovery; on average it takes a full year, although many people feel much better around three months. There is still a lot of healing going on for months after the three month mark, but a lot happens in those first three months. Walking around for your daily activities really does help with extension. If you consistently practice walking with a longer stride, as Jockette mentioned, (and notice how it tends to stretch the back of your knee more), it will help over time. Just don't stretch it too far early on so you don't over-extend it. I've done that and my knee had an instant hissy fit each time. I also purposely straightened my leg as much as possible when standing in place, and noticed over time how much more it straightened.
Time is our friend with this recovery, even when we don't think it is. If you look back at where you were at two weeks, one month, six weeks, and even two months, you will see that you are improving. It just seems so slow and takes so long when we're looking forward, but looking back helps with our perspective on how far we've come and how we're doing.