I reject the possibility that this is a rocket-based phenomenon as the MSM puts forth. We've seen rockets and missiles tested or fail many times before, and their contrails don't glow like a bright neon sign after the fuel rapidly combusts.
Nevertheless, I am of the view that "they" can do some things to trigger the spirals for a variety of purposes, including quasi-religious ones (e.g. Norway in December 2009). Assuming that space is electrified plasma, and that the Earth's atmosphere acts as a dielectric, and that "they" have relatively low power (say < or = 100 MW) equipment capable of poking a hole in this dielectric, I would guess that this is the true means to harnessing such EU powers from afar, or at least inviting them into the Earth's atmosphere where they otherwise wouldn't come in by themselves. Imagine if you can create a 10,000 MW inrush event from a strategically placed 10 MW pinhole. I think that's the sort of thing that "they" are playing with. I would guess that the events are short term for this reason - much like when the dielectric in a capacitor breaks down - a lot of stored energy dissipates and continues to leak unless the dielectric is repaired - as the atmosphere may repair or restore itself if left unadulterated.
However, if this is indeed naturally occurring EU phenomenon (I think the Venus events were 100% natural), then this is all about electrical conductivity and electrical paths. It stands to reason that so many spirals occurred or were cited in conjunction with the Venus transit event as the planetary alignment with the Sun and Venus and Earth would make a straight shot for the electrical energy to flow.
One other thing that I have noticed after viewing several of similar videos: They seem to occur within about 1 hour before dawn (or possibly after dusk). This would suggest that when the electric "rays" of the sun hit the earth or pass / pinch around it almost tangentially, and pass through the atmosphere only when conditions are optimal for the conductive path. I would guess that if "they" are provoking the EU, that "they" are timing their efforts in accordance with this principle, so that the result is something that can be both seen and the most effective. I would guess that if it is too bright outside, these things can't be seen; and for some reason (maybe power levels) anything but a tangential conductive path doesn't effectively illuminate or manifest.
Here are others worth serious consideration (hopefully "they" didn't yank any links):
Australia
http://www.youtube.com/watch?v=9pgaw6qFbdk&feature=related Australia raw
http://www.youtube.com/watch?v=Iybv4QhNPB8 Australia
http://www.youtube.com/watch?v=oW2h8U5GTEc Norway
http://www.youtube.com/watch?v=IyWrxY15s6Y&feature=&p=943621FF03262718&index=0&playnext=1 Norway
http://www.youtube.com/watch?v=CxA0Asq2YDg&feature=fvw China 2
http://www.youtube.com/watch?v=V8gWv75bK3s China 3
http://www.youtube.com/watch?v=QJxJxfU3Q5I&feature=related China 4
http://www.youtube.com/watch?v=xMU4hXkF720 China 5
http://www.youtube.com/watch?v=FhVv8eqrRfI&feature=related China 6
http://www.youtube.com/watch?v=Ylk2DKLrJIw Russia
http://www.youtube.com/watch?v=v2icGX61uTM Russia
http://www.youtube.com/watch?v=G-mq0zLIkkw Mexico
http://www.youtube.com/watch?v=5aOKZDEqxjc Vandenburg
http://www.youtube.com/watch?v=Al11l5SwhAk&feature=related Dublin
http://www.youtube.com/watch?v=W9HBv6SwSTk Santa Monica
http://www.youtube.com/watch?v=z87YtLdKOzs&feature=relatedIf you watch all the footage available of the original Norway spiral, you will see the straight tail start to slowly corkscrew more and more and increase in size (what appears to be wave amplitude) after the spiral dissipates (within 10 minutes). The result is a chain of "rams heads" or "seagulls" as identified in rock art and by Perratt's articles.
If you look at the Santa Monica one, it looks much more along the lines of man made. It is, nevertheless, occurring near dawn or dusk, and if you look closely you will see a smaller and more pointed one that looks like it is naturally occurring like those in the other videos.
In any case, it would be interesting to compare the dates of the above events with other planetary alignments or comet proximity (or possibly earthquakes). I am also of the view that these will continue to ramp up in siting frequency and intensity in accordance with a variety of prophetic events.