Plainly and simply, prices are at their lowest point of the day.  And though this STILL leaves MBS over 101-00 on the 4.5 and the 10yr is still under 3.35 (yesterday's high).  As has been the case with many alerts recently, we're putting this out only because we're compelled to by the break of intraday lows.  This is by no means an indication that MBS prices will move lower through the close.  Range-bound choppiness is likely until the events of this week and to a lesser extent, next week transpire.  Prices may be up, down, or sideways by the end of the day, but just be aware that some lenders almost always reprice for the worse when we hit lows of the day.  Other than that, I wouldn't adjust your "big picture" on the direction of rates just yet...  Bottom line: if you have the risk tolerance, and can weather an intraday reprice for the worse (minor one), I'd hold off for the time being.  We'll let you know if it gets bad enough to change that stance (or good enough for that matter).