Ronin,
$1500 should buy you a really very nice bike. You can probably spend a little less to spend more on accessories. One decision to make is if you want a more race oriented or commute oriented bike. Racing oriented bikes are honestly very fun to ride, but can be less practical. They may not have rack mounts (should you want a rack) and if they do, the chainstays may be short enough that it's hard to set up with panniers without heel strike. Race bikes also often lack fender mounts, making fender installation harder. They also have limited tire clearances, and running wider tires can be more comfortable on rough roads. They may feature relatively high gearing that may be rough if you're not in very athletic shape, or if you're carrying heavy loads. They also are designed to be set up with a fairly aggressive fit that bends the rider's upper body far forward for aerodynamics and biomechanic efficiency, but this can be less comfortable and some riders may find it hard to bend their neck up to look ahead. It should be noted that fit is pretty variable and you can get a pretty upright fit on many racy bikes. That said, if it weren't for fear of theft and the occasional need for fenders, I'd probably do most of my commuting on my carbon road bike because I can generally get away with a relatively light backpack, and it's a fun ride.

A good compromise might be a decent cyclocross bike--most can run fenders and racks, but are still fast, performance oriented bikes, and as a bonus you can do some moderate off road riding as well. One thing to be aware of is that race-oriented cyclocross often features 46/36 tooth cranksets, which is narrower in range than is typical of most mid-tier road bikes (which now generally come with 50/34 compact craksets) and could make some steep climbs (or rides with luggage) a little rough. Some cross bikes however aren't particularly specced out for cross racing out the door, and will come with either 50/34 compact cranksets, or triples.

For racier bikes, many brands come with two different geometries, one typically being a "race" geometry, and one being an "endurance" geometry. The race geometry will typically have a lower headtube (allowing you to set your handlebars lower), and shorter chainstays (for snappier handling), and may be designed with a slightly more compliant ride. With your budget, you should consider mostly aluminum bikes with Shimano Tiagra or 105 drivetrains, or Sram Apex drivetrains, although you might find good deals on carbon or better specced bikes in your price range. Some example race geo bikes would be a Trek Madone 2.1, Specialized Allez Mid-Compact, Cannondale CAAD10-5, or similar offerings from a number of brands. Those same brands endurance bikes would be a Trek Domane 2, Specialized Secteur, or a Cannondale Synapse. I don't have strong feelings about those 3 brands in particular, they're just well represented in my area. Also the Surly Pacer is a very sanely specced bike if you're interested in a somewhat more practical bike that's also made out of steel, and will let you run a rack and fenders at the cost of maybe 5 lbs against the other bikes I mentioned.

Some good general purpose cyclocross bikes might be the aforementioned Surly CrossCheck, and the Specialized TriCross is also nice in that it's really designed more as a general purpose bike than a cross racing bike, and is available with wide range gearing (including a triple).

Hope you have fun. Buy what you like, preferably from a shop you like doing business with.