Here is your link:
http://yfrog.com/04tomato007jx

The bumps on the stems are probably adventitious roots (I can't tell from the photos). Generally adventitious roots form wherever there is moisture, so you will see them growing where a stem touches the soil -- or simply in humid weather! In rare cases, they form when the plant needs more moisture than it gets from its normal root system, and are an indication of problems with the existing root system, or with the vascular system that transports water and nutrients through the plant.

The yellowing/browning may indicate inadequate water, inadequate fertilizer, high temps, or many other conditions. Again, the pictures don't show enough detail.

Tomatoes growing on this plant should be fine. If the fruit have spots, cut out the spots.

Topsy Turvy planters seem to have a lot of problems, though apparently a lot depends on what variety you grow and the weight of the fruit. Here are some other discussions about them:
http://search.gardenweb.com/search/nph-ind.cgi?term=topsy+turvy&forum=tomato&forum_name=Growing+Tomatoes

I've been growing cherry tomatoes out of the bottom of a hanging 5 gallon pot for 10 years. It works well, but I am tired of cherry tomatoes (too much skin for the small amount of flesh), so I am going to try a mainseason next year. It will be interesting to see if the fruits stay on the vines as they grow larger.

PS - My neighbor has a Topsy Turvy. The plant died. I don't think they hold enough soil or moisture for a tomato unless you try a specific container type.

Root initials.