OSU Blue, which is commonly distributed at Seedsavers and can be found several places on the web, is an early version of the P20 selection. It does NOT give high levels of anthocyanin in the fruit. Look at any of the photos of it on the web and compare to this photo of the pure P20. The fruits in this photo are up to 2 inches diameter and about 2 weeks from ripening.
http://upload.wikimedia.org/wikipedi...Bluetomato.jpg
P20 is an advanced selection from Jim Myers at OSU. It develops extremely dark fruit that can be so dark they are jet black. The stems and leaves also contain high levels of anthocyanin. Jim Myers has stated that he will release an official version this year that will combine the best traits they have been able to integrate to date. I am trying to get seed.
Jim made the genetics available about 4 years ago now via a non-propagation agreement. This means you can breed with it but you can't sell the original seed/plants. I got an early start of the seed and have been working with it to develop highly colored fruit with improved flavor. The first year I grew the plants I got a range of plant and fruit colors from barely darkened fruit to one plant that produced jet black tomatoes. I have been saving seed from the jet black line ever since.
At least 50 other growers also got seed from Jim over the last few years and have been crossing and selecting to get larger fruit with better flavor. I expect that within 2 years blue tomatoes will be commonly available and no longer much of a conversation item.
DarJones