We're emailing all day, and Blackberry Messenger is our secondary source, which is another form of texting that's free for us with our blackberries. We don't do phone calls too much because emails and messages can be responded to whenever the other has time. Some seem to have a view that this means we're "checking up on each other" and I want to clarify that this doesn't mean I don't trust my husband or that he doesn't trust me.
We have five kids and mornings, evenings and weekends are filled with activities. We are at a point in our lives where we really can't get away for vacations together or date nights and we just don't get many opportunities to talk and connect. We message each other during the day to talk about schedules, finances, our kids, our frustrations, or whatever.
We're not terrible at our jobs either. I'm a housewife so I can do this pretty much anytime I get a second to sit down and check messages. My husband is a great employee who is devoted to his job, but when he has a break or lunchtime, he sits down and reads my messages and responds and sends me some messages to read during the next time I have a minute. This is how we plan vacations, problem-solve issues with the kids, etc. and it works much better for us because we're not rushed and we can take the time to talk things through and hear each other. Phone calls and "real life" conversations are usually rushed and interrupted and not nearly so productive. It's probably a stage of life thing for us, but email and texting keeps us close and connected!