I have Shimano triathlon-specific shoes. They just have one big velcro strap which has a notch so it can stay open if you clip them into your pedals in transition. They also have a drain in the bottom so any water from the swim that runs down into your shoes has a place to go. I wear them without socks. Just got new cleats and they look a little rough, but they're still going strong after 4 years of racing.
Mine are an older version, but essentially this: