Yep. Looks like it.

Info from the University of CA
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7400.html

Here is a link that might be useful: giant whitefly

A simple sharp water spray is often enough to knock these buggers off the leaves and will do no harm to the predators of the Whitefly. Insecticidal soap, many dish "soaps" are detergents that can do more harm to your plants then the insect pest would, so if an IS is to be used and you wish to mix your own be sure to get real soap, not a detergent a petroleum byproduct.
Neem Oil products are broad spectrum poisons, like all the other insecticides, that must be used with care so beneficials are not killed off with them.
Since insects provide a food source for many other creatures, other insects as well as birds, toads and frogs, snakes, etc. of the some 8,000,000 identified species only about 8,000 are considered pests.
The best way to keep your plants from being attecked by these insect pests is to grow them in a good, healthy soil so the plants are strong and healthy and better able to withstand an attack by the pests.

Thanks for replies. At least now it's confirmed that it's the white flies.

kimmsr, yes, I completely agree with you as to detergents, insecticides etc. I just moved here to the US about 9 months ago and finding organic and "healthy" cleaning stuff is still a jungle to me. It seems to me the average American uses LOTS more cleaning liquids, powders, sprays etc than I have ever seen in my entire life ;-))

Finally I found Ecover and Seventh Generation here, though I do know that they also contain SLS. Well, I'll get off my soap box and try and do something about my white flies, who by the way, seem to stay at the same level. Haven't seen any flies since yesterday afternoon and no more infested leaves.

As for good, healthy soil, that is also a bit of a jungle to me. Though I have learned a bit over the last couple of months. I think next year we will be a lot better prepared. We did till our soil (with is mostly clay, probably loamy clay), mix with compost and garden soil. Well, we'll get there. Just so hope we can keep the white flies away. Cut worms and Horn worms I got rid of by plucking them off the plants.... Hours invested - but well invested I think.

Thanks again.

umm, folks who don't live or garden in CA, TX, or FL need to understand that giant whiteflies are *not* your average whitefly.

It will require more than a harsh water spray to deal with those giant whiteflies.

I suggest you contact your counties Extension Service office to determine the recommended management.
Locate your county's office with this map
http://www.csrees.usda.gov/Extension/

Here is a link that might be useful: locate your county's Extension Service office

Thanks Jean, we do see some lady beetles and green lacewings on our plants, that seems to be a good thing. Water spraying will NOT take care of it, you're completely right there. I'm still a bit apprehensive about using oil or insecticidal soap. Checking several times a day and so far only 1 affected leaf today. So still hoping ;-))

The UCIPM website that jean linked tells us to do just as I described.

kimmsr, yes, it does describe the water spray method, but it just doesn't work with these. They were glued to the leaf. I plucked off the infested leaves and the last couple of days have been rubbing off the tiny, tiny circular trails, hoping that will take care of it. So far I haven't found any today ;-) I will resort to soap or oil if the damage doesn't settle.