I'd echo Mystery Meat's point, though I haven't written many columns.
As a reader I'd say using "I" has a place, but only if you're talking about something that specifically happened to you, such as an anecdote of some sort. If you're writing a column about taking your kid to their first baseball game and you do backflips to avoid writing "I" then you may want to see a therapist and get some things off your chest.
Simply saying "I think" every time you're interjecting opinion though is usually a tip-off of a rushed column, to my eyes.