If you are planning to take lots of trips in Merida with tour companies to places like Los Llanos and Catatumbo or to participate in things like Canyoning, Paragliding, Mountain Biking, Rafting, etc, you should bring U.S. dollars to pay for these as they will be much cheaper. Most of the tourist companies in Merida seem to use the unofficial exchange rate or a rate around US$1 to BS4,000 (BsF4) for the price in dollars.
For example, for canyoning, the price in November 2007 was US$45 but BS.180,000. A huge difference in the cost if you are taking money out of the ATM to pay for things as you would be paying US$90 for the trip (official exchange rate is US$1 to BS.2,150/BsF.2.15.
Therefore, I advice you call ahead to find out prices of things you would like to do and take the dollars with you to pay. A lot of tour companies only accept cash or a bank transfer to pay for the trips.
Clothing/Shoes/Weather Gear: It can get a little chilly at night sometimes in Merida and you may need a jacket when at the top of Pico Bolivar. So if visiting Merida, make sure you bring a rain jacket or sweater just in case so that you can stay warm. The climate here is very different to other parts of Venezuela.
Luggage and bags:
If you go by Guamanchi tours into the Andes they will supply you with the needed gears and clothes.
Clothing/Shoes/Weather Gear: a pair of trainers could be a good idea to have.
Toiletries and Medical Supplies: looperamide if you get a running stommach.
Photo Equipment: Good to have, but remember the risk of getting to much attention and being robbed. Create a backup system for your precious pictures!
Camping/Beach/Outdoor Gear: Can be rented if not supplied by your local guide.