The story hasn't changed on seed size. If you are planting seed grown in 2014 under very good conditions, where yields were up and ear size up, kernels were likely smaller because they were closer together. That usually means smaller seed and more medium flats vs. rounds. You get more rounds when there are fewer kernels on the cob and seeds have space to "round out."
Experts suggest checking your seed bag tags or tags on seed boxes in bulk to know what size you have. If you are going to run your units on a test stand, consider running each lot of seed on the stand, especially for vacuum units. Know what settings you will need. In some cases you may need to get a special plate to plant smaller seed.
Soybean seed could be the opposite, with large seed and fewer seeds per pound. Make sure you have the right planter equipment in your toolkit to make changes so you can plant either large or small seed properly.
Some people go to aftermarket manufacturers for planting units and retrofit existing brand name planters with the equipment, such as eSet from Precision Planting.
Pete Illingworth, who is a mechanic and the planter operator for Throckmorton Ag Center, a Purdue University farm near Romney, has converted to eSet units on the John Deere air planter he operates. He believes that by using the right disk for the meters, he can handle a wider range of seed sizes and shapes, especially when planting corn.
Illingworth also believes now is the time to anticipate what situations you might encounter during the season so that you have the proper equipment and can make any necessary adjustments quickly once the season starts. He believes in pre-season planter maintenance so the planter is ready to roll once field conditions are right.