This image is taken from the Lasco 3 detector at http://sohodata.nascom.nasa.gov/cgi-bin/data_query on Aug 05
In one video it is correctly pointed out, from the Wiki page, that the nex transition of Venus is not until 2012.
The speed the current object is moving is also compared with the transition made in 2004, which took 11 days.
A transition of Venus, per definition, is when it travels in front of the disk of the sun, as seen from SOHO and the earth.
Today it's traveling behind the sun, so the crossing will take a much longer time.
If you look at http://gunn.co.nz/astrotour you can clearly see this, and you can also see that Mercury will probably come in from the left in SOHO's view sometimes around Aug 10-15 or something.
Edit and update 6 Aug 2011 :
In the "NEW! 8.5.11" video at around 4:30 it's said that the current object on SOHO Lasco3 isn't diminishing in the same way Venus did in the end or 2009.
If you look at the superimposition of two SOHO images taken when the 2011-object is at about the same distance from the sun as 2009-Venus you see that it indeed seems slightly larger today, but you can also see that I had to move the 2009 image upwards and to the right to make the solar-mark fit, which indicates that SOHO (quite obviously) isn't in the exact same position regarding the sun as it was in 2009. That might account for the percieved slight discrepancy between the objects.
And another thing to consider : if this isn't Venus, then where is it? It should be in SOHO's view right now...