I'm very bad at this because I've been lucky with my plants and not had many pests. I can only give a couple of suggestions : The mention of the web made me think of red spider, but the spots look a little like mealy bug, except that I think that is usually found at leaf joints and where branches start, Have you been painting recently? It also reminds me of the splashes of paint my husband got on my plants from time to time when decorating :) Of course, I suppose you could be unfortunate enough to have red spider, mealy bug and paint splashes at the same time. I wonder does anyone else here have any ideas? There are real experts here, let's hope they can spot your problem.

You may have aphids. There are many kinds; white, black, pink, and green are the colors of those which attack tomatoes. Some life stages have wings, others don't. It is common to see more than one life stage together. photos of (mostly) black aphids on (mostly) tomatoes Aphids suck plant juices, stealing energy from the plant. To get rid of them, you can squish them by hand, wash them off by spraying water (but the splash may knock disease-causing bacteria or spores from the soil onto your plant), spray with a solution containing Neem oil or soybean oil (available at your garden center), or spray with water to which a small amount of mild dish soap (not anything that says "detergent") has been added. This seems to be the ultimate aphids-on-tomatoes thread: http://forums.gardenweb.com/forums/load/tomato/msg0518184110959.html

Very hot weather will cause blossom drop; see the FAQ linked at the end of the post. There is a natural joint in the stem about a centimeter from the blossom: that's where the stem snaps easily when you pick a tomato, and it's where the stem will break by itself when a blossom is not pollinated (as well as some other circumstances). The small black-ish bugs may have been aphids, sucking insects which feast on plant sap. They come in different colors (IIRC, the ones which like tomatoes are black, white, green, and pinkish?). Some have wings, but most don't; you will see different ages/sizes together. A few shouldn't be a problem, but they breed incredibly fast, so you did the right thing to spray with insecticidal soap. Some people just squish them. Try to keep the plants consistently moist -- but don't overwater. *lol* -- no one ever promised life would be easy.... Here is a link that might be useful: http://faq.gardenweb.com/faq/lists/tomato/2000083030027695.html

I'm comfortable calling them root aphids. The symptoms seem to fit and they do seem to look right (at least in person). I've already discarded both plants and will have to keep an eye on the other ones that were nearby. We used a commercial potting mix, but I can't remember which one- it was something different than normal and the bag got discarded. I think there must have been contamination of the soil at some point, because the 2 plants were definitely thriving before we repotted. I suppose it's possible that they had a small infestation and then the stress of being repotted allowed the aphids to get the upper hand...but I tend to believe it was the soil, since it was also contaminated with fungus spores. Thanks for the help