The 5 PM update is pretty much a continuation of what's been happening for the last several days -- more intensification, more inching the official forecast track to the east, continued resistance to moving east from the one outlier computer model.
At 5 PM, Irene's center was located just north of the east end of the Dominican Republic. The storm is expected to remain offshore, moving along the north coast of Hispaniola. There will be some interaction with the mountains of the DR and Haiti, but the storm center will be over open and increasingly warmer water as she moves NW, reaching Category 2 intensity Tuesday night.
Hurricane Irene is now expected to reach Category 3 strength (111-130 MPH) by Thursday afternoon. That makes her a big nasty storm. In the careful language of the National Hurricane Center, the general description of a Category 3 storm is "Devastating damage will occur."
On Thursday afternoon, the center of the official projection is shown about 120 miles due East of Miami. However, the National Hurricane Center warns against looking at the middle of the track because of the wide variance in accuracy beyond 3 days in the future.
Further up the road, landfall (which had been expected on the central Georgia coast has now moved through SC to the NC/SC border (Myrtle Beach) area. That's a result of the projected track of the storm slowly inching to the east.
Again, however, it's important to remember that this thing could be 200 miles one way or the other from the center of the projected track. To get an idea what that means, if you look at the circle for Saturday afternoon, the storm center could be anywhere from Jacksonville, FL to Baltimore, MD! It's also important to understand that a hurricane is not a point on a map, but a very broad area of very bad weather. Regardless of where the center is, there might be hurricane force winds across a front more than 100 miles wide.
It's still too early to call, but I think by tomorrow night (Tuesday night) or Wednesday morning, we'll have a much more clear picture of where the storm is going.