Dynamic

Dynamic mics are capable of handling louder audio sources which is why they are often seen on stage.  They often also have a smaller pickup area which means the sound source needs to be closer to the mic.  An advantage of this could be that it may pick up less computer hum, chair squeaks, paper rustling etc.  It'll generally pick up less of the echo sound of an untreated room because it's not really capturing the reflected sound.
Dynamic mics are less sensitive and may not represent the tone of a voice over or intimate guitar recording as well as a condenser mic.

Other Things to Consider

A high end condenser mic will almost always set you back more than a high end dynamic mic but dynamic mics are a bit more durable.  You should always handle a mic very carefully because they don't like being dropped but the dynamic mic is a bit more shock proof.
A great tool that I often use is the Rode Sound Booth.  This gives you the ability to listen to the same audio recorded with a variety of different microphones.

So Which Mic should I Get?

This totally up to your personal preference.  If you're someone who has a mobile setup with multiple mics that is constantly packing and unpacking, a dynamic might be a good option.  You'll get more mics for your money, you know you'll get a reasonable recording from the mic even if the room isn't perfect and it'll handle the odd bump here and there.
On the other hand if you're someone who is always recording from the same treated room with the mic mounted on a stand and the best audio quality possible is important to you, maybe a condenser is the way to go.  
Personally I have a Rode NT1-A (condenser) for my voice overs permanently setup in my studio. When I'm recoding podcasts I like having the ability to record from anywhere with multiple guests.  I have have four Rode Podmics, these plug into a Rodecaster Pro which records to an SD card.

Thinking of starting your own podcast but don't know where to start?  Visit www.voicemedia.com.au.