The current method of warning people that they've incorrectly entered field data is far from satisfactory. It's too easy to miss the Explanation Mark in a red blob, especially on smaller screens. A far better way of warning people is to have a popup which lists the errors. How it's implemented and what it looks like is something for the developer to decide, but I liked the message used on Wickle (now defunct) which is similar to the example below.
Yes, my users have often complained of the little red circles things as well.