Technical Stuff...

Handle
Dual density handles (Salomon Arctic) tend to be more comfortable as they can feel slightly softer and normally grip better. Mono-material handles will be cheaper but won't feel as comfortable. Women's specific poles sometimes use a smaller handle (K2 3 Karat).

Strap
Cheaper poles will use a simple system of nylon strap and pull-through locking system (the FX 15x25 on the Scott 540), this is easy to use and very effective. Wider straps may feel more comfortable (Salomon Patrol), though the very best versions will use padding and/or Velcro closure systems (the Notch Strike on the Scott RS-12).

Shaft
The shaft can be made from aluminium or a composite material. The higher the number of the aluminium the better grade, meaning it has a better strength to weight ratio (7075 on Scott Team Issue, 5083 Joystick Spicolli) but it will be more expensive. Some women's specific poles will use a narrower diameter to reduce weight (16mm on the Dynastar Exclusive Sensation). Composite shafts are lighter than aluminium, something you will notice when you swing a composite pole. The strength on these can vary (a K2 3 Speed is exceptional value for a composite shaft, but not as strong as the Carbon Matrix on the Scott A-12 which has enough strength to be made in a 13mm diameter).

Basket
Wider baskets will not sink in soft snow as much as a narrower one, so choose a pole with a big basket if you intend to ski off-piste (the new F-Ride on the Scott Punisher). Narrower baskets suit piste skiing and park use (the 58mm 3.6 Disc on the Scott Team Issue). The Joystick JP PRO comes with 2 sets of baskets so you can swap from park to powder without compromising.

Tip
Most tips will be made of steel to provide good 'bite' on hard snow and strength to withstand knocks and bangs. Carbon based tips are more expensive but will cut into firm snow exceptionally well.

Ski Pole Sizing
Position your elbow next to your side and bend your forearm 90° so that it is parallel to the ground. Take the ski pole and turn it upside down, putting the handle on the floor. With the ski pole vertical, position your hand under the basket. If it is the correct size your forearm will still be parallel to the ground.