Here's my list of the best cards in the set so far. These are cards that should be good for any strategy- look to these cards to keep in your deck, or bring in from out of faction.
Best Runner Cards:
Diesel: Card Advantage!
Sure Gamble: Much more action efficient than Easy Mark or Armitage Codebusting.
Special Order: Right now it's the only deck searching for the Runner, and the best way to get just the breaker you need at the right time.
Best Sentrybreaker: Femme Fatale: Not only does she break Sentries, she lets you pick a 2nd ice to break cheaply. Only downside is that she is pretty expensive, and prohibitive against large sentries.
Best Wallbreaker: Battering Ram: Most money efficient during the endgame.
Best Codegate Breaker: Gordian Blade: Same as Battering Ram
Best Allpurpose Icebreaker: Crypsis: Having to spend time to get tokens seems like a pain, but in the long run its much cheaper than Wyrm.
Netshield: Very awesome against Jinteki, or anyone with Netdamage.
Sneakdoor Beta: Forces the Corp to defend Archives. Good for anyone, if you can find the memory.
Hardware & Resources
Akatatsu Memchip: Currently the only non-console way to get extra memory (unless you're playing Djinn, which only works for the virus deck.)
Icecarver: Will save lots of money over the long run.
Wyldside: Well worth the time investment over the long run.
Best Corp Cards:
Anonymous Tip: Card advantage.
Scorched Earth: Instant victory
Archived Memories: Recurse your best cards.
Neural EMP: Direct damage, no need for tags or tracing.
Best Sentry: Archer. Forfeit an agenda for an extremely efficient killer.
Best Wall: Heimdall 1.0: Brain damage and 2 end the runs.
Best Codegate: Tollbooth: Very expensive to get past.
Melange Mining Corp: For when you absolutely need money right now.
Project Junebug: Probably the best trap card, since it can kill the runner outright, and has a low buy-in for out of faction play.
Redherrings: Cheap for you, annoying for the runner.
Zaibatsu Loyalty: Make a run irrelevant for 1 bit.
Best Agendas (a little tricky, since all of the faction agendas are in-faction only.)
Accelerated Beta Test: You'll want to have your archives protected or know what's on top of your deck (Precognition, anyone?), but free ice is free ice.
Breaking News: A same turn agenda with no downside, or hold onto it for next turn for bonus tag goodness.
Priority Requisition: Valuable, and the free rez can be worth more than you paid into the agenda.