Whether you regularly email your client or send traditional snail-mail, consider including some market statistics. We like to use a Good, Better, Best framework.
GOOD
If you don't have a lot of time, just send the Market Infographic or Market Review. You can print it to a PDF or take a screen capture, and then send it to your marketing list.
BETTER
If you want to do a little more, send one of the above dashboards or several of your favorite charts and add a bit of commentary. This is your chance to show that you're an expert in the area by sharing what you know, or sharing things you find interesting.
BEST
By far the best option would be to tailor what you're sending (from "Better" above) to each client. This of course means that you need to have your database or marketing list somewhat segmented. For example, if you have clients in the Luxury market, they likely don't care about what's going on in the overall region, but would appreciate updated stats on their specific neighborhood. Or if you have clients that are only interested in Condos, send them just the Condo update.