The two major things that people have been asking about are gear (and how to choose which gear to use) and rotation (*). While both are major topics in their own right, I would like to focus on current gearing for the spriest.
The entire focus of a spriest is to maximize damage-per-second (DPS) while also providing appropriate utility to the raid group. Much of the utility brought by spriests is in the form of buffs/debuffs that are applied simply by the use of our normal combat mechanics. Thus, we can focus on maximizing our DPS, which will in turn maximize our utility.
One of the ways to maximize DPS is by properly gearing a spriest, which has changed recently (in patch 3.3) due to how haste now affects certain damage-over-time spells (DoTs). This change basically allows DoTs to tick faster depending on the amount of haste that you have available. Note, however, that with the current implementation, SWP does not benefit from haste (so you will not need to re-cast it during Bloodlust/Heroism).
Anyway, if you are interested in min/max-ing your spriest, I would suggest stopping by the BRG (Best Raid Gear) forums on www.shadowpriest.com, but make sure you are looking at the information for the current patch (3.3). If you are not really the min/max type of player, but would rather settle for a general idea of how to gear, just follow this simple rule:
Hit (**) > Spellpower = Haste Rating > Critical Strike Rating > Spirit > Intellect
Keep in mind that is using raw (rating) values, so 1 point of Spellpower would be equivalent to 1 point of Haste Rating (not 1% Haste).
While that is the general rule, you may want to also keep in mind that Haste is a stepped type of stat, where 1 point of Haste Rating may not be entirely equivalent to 1 point of Spellpower. In fact, depending on what your current haste rating is, it may be significantly higher than spellpower. If you were to see a graph of the two, it would look something like the image above (though likely more of a curve than entirely stepped). The idea is to get enough haste so that your spells coincide with your global cooldown, which (if I remember correctly) happens somewhere around the 600 Haste rating and 900 Haste Rating marks (a.k.a. the sweet spots), though I wouldn't quote me on those numbers.
So, with that, I wish you good luck in picking out your new gear, and hope that I have steered you in the right direction.
See you in the Shadows,
* Spriests don't necessarily have a "rotation" to speak of, but should focus on using a priority list.
** When under hit cap.