Exactly: once you put your stuff in panniers, or other bags, and off your back you will feel a difference! Particularly in hot weather it's nice to have a breeze down your back. It's a HUGE difference and it looks like you carry a lot of weight and your commute is long by NYC standards. IMHO two rear panniers is the way to go: you can haul 30lbs easily and won't even tell.

If I may I suggest: a Topeak Supertourist rack and Axiom Typhoon waterproof panniers. Axiom also makes a smaller version, the Monsoon, but they'll be too small. I actually have all four of them on my commuter They really take the worry off of getting your stuff wet. I rode with them thorough Winter's sludge and heaviest downpours and none of my stuff got wet.

You're doing very well considering the length of your route and the weather. Be careful, take it easy, drink a lot of water all day. Too much heat makes you tired and less alert so make sure you stay hydrated! Take advantage of shade whenever you can. if I stop a a light, for example, I try to remain in in the buildings' shadows.

My commute was close to 1:30, now it's under 40 minutes. Once you get your set up with panniers, get more practice, become stronger and optimize your route it WILL get better.

Regarding lights: stop, really, you don't gain that much by running lights, you risk getting hit and you CAN get a ticket! There is a guy in General Biking forum complaing that he got a ticket for running a light: $270, ouch! I got stopped once too, but I was super nice and apologetic to the cop and got away with a $40 summons. I ve been trying to be good since then. Often, the urge is too strong, but I'm getting better. This dude started acting smartass with the cop "I didn't know bikes were supposed to stop at a red light" and he got the max fine.

Ironically, a bike activist was killed last year on Queens Blvd when he rode through a red light. I used to run more lights, now being more careful and trying to set example and I didn't notice any increase in my commuting time. I was told that most city lights are synced to vehicles moving between 17-19 mph. Once you get used to your route you may be able to figure out and time the lights on a bike better than in a car. I can ride on 1st Ave from 14th to 34th without stopping most of the time.

So good luck and come back, tell us how it goes!

Adam