The USDJPY held below the 100 hour MA on the recent move higher, and that seems to be the dominant technical clue for the pair today. The 100 hour MA also corresponded with a trend line which enhances the levels importance. Traders can lean against this level on rallies.
On the downside, the price is approaching some support trend lines (see chart above). The 78.83-88 area is where these lines come in. A break below this level should open the door for further downside momentum.
The next target on a break would be the lows from Monday at the 78.679. A move below that comes the 78.60 level. This was the low on June 15th. The 78.30 level was a high ceiling back in the November to January period (see daily chart). Finally 77.65 is the low for 2012.
Holding support, will take some steam from the sellers but ultimately that 100 hour MA and trend line will need to be breached to take the bias away from the sellers.