http://sohowww.nascom.nasa.gov/hotshots/2003_05_07/
Watch the movie!
Ok, I’m a weather/space geek so maybe nobody finds this as cool as I do.
Venus goes across next year, I can’t wait!
Space geek checking in 
You’re not alone, ** Bruce. **
The transit video is awesome, can’t wait for Venus.
Wow, this beats the heck out of paper across Uranus.
Freddie?
Sorry. Nice video.
One more joke of that sort, and s’welp me, I’m gonna start a campaign to revert to Herschel’s original name choice!
Then let’s see you make double entendres out of the planet “George”!
(sphincter tightening…)
Woah… an eclipse.
The astronomy sites state that this is a very rare transit, happening only a few times a century. Does anyone know why it’s so rare? Seems to me that if we are on roughly the same plane as Mercury and moving around the sun at a different rate, that we should see transits on a fairly regular basis.
They announced it on the radio as I was driving to work yesterday. I thought, “Cool! I can check it out as I walk to the office, or maybe during lunch!”. Then they went on to say you needed a telescope to see it. “Ah, nonsense!”, I thought, “Surely my superb vision will do!”. The announcement ended with the announcer stating that Mercury would be the size of a 1 euro coin…
… at a distance of 370 meters.
:dubious:
I gave up after that. 
I looked but could find it… when next year will Venus follow suit?
From cnn.com :
I guess we’ve got plenty of time to practice our pin holes and poster board.
Even better than a full moon!
The key point to the answer is in the question: “…we are on roughly the same plane as Mercury…”
The planes of our orbit and Mercury’s intersect. But only when both planets are at a point in their orbit where they’re both in line with the sun and at that point where the planes intersect will you get a transit.