I am a new Savage (previously a D&Der - 1e and 3e, looked at 4e but just not interested). Here are my thoughts:
From the DM Perspective:
As others have said, prep work is a breeze. Once you have enough experience, you can run other system's stuff and convert on the fly (I am not quite there myself, but I can see it). It feels like the 4e approach in that monsters are simplier but there is system stucture underneth it (note the rules tell you DO NOT BUILD A MONSTER OR NPC LIKE A PC - awesome advice).
The system has an overall narrower range of power progression. As someone on PEGs boards put it, you do not go from n00b* to god, but from good to great.
*4e obviously changed the starting point a bit.
Some have touched on the no-hit point approach. This is a HUGE advantage for me. Extras (minions or weak monsters) are either up, shaken, or down - hardly any tracking. Wilds (cool monsters and PCs) are up, shaken, up to 3 wounds, or down. At the table, poker chips are perfect. White is shaken and red are wounds - stack'em up! I have run several sessions without writing a single thing down in combat (think loooong and hard about that, you HP junkies
). No more questions about "well, how hurt does it look?" - its out there on the table. All my attention is on the table, not a computer or paper to track stuff.
The SWEX just oozes with ideas. Since the system works well across genres, I am interested in exploring other gaming concepts. Sure, d20 had all that, but all the feats and costumization just did not seem worth the hassle.
PCs:
I find there is enough Crunch and Fiddly bits to keep players happy about character creation, but not enough to overwhelm players that are not huge into systems. Somewhere in the middle of 2e and 3e in complexity (note that making a brand new PC takes very little time if you have the concept in mind, only higher "level" PCs take some thought).
Tactics matter. While fast and furious, it is not just throwing dice. Range weapons are deadly - TAKE COVER! Tactics are needed for the BBEG as they can shrug off hits.
Bennies are fun! In D&D, hit points are the currancy of chance. That is what keeps the hit level PCs from being immediately eaten by a dragon. In SW, its Bennies - like action or plot points. You can reroll if the dice are against you or soak up big hits.
Hindrances rock - other systems (like Cortex, I am sure many others) have hindrances/disadvantages. The lead to a bit of min/max, but they also lead to roleplay. You earn more Bennies by roleplay/cool actions - and playing to your hindrances instead of metagaming is a quick way to earn a Bennie.
Exploding dice are fun (keep rolling if you max out a die). Yes, it can hammer you, but it builds excitement at the table when a player keeps on rolling.
My group, all D&Ders, picked up on it really quick. They have not gotten all the intricacies down, but after 3 or 4 sessions the system faded into the background (except for Bolt - a powerful spell that is rule intensive - if you figure out Bolt, you can run anything).
As others have pointed out, there is a very active community.
Finally, I found The Making of SW to give great insight to how the system plays and the philosphy of the mechanics. That really spoke to me.
http://www.peginc.com/Downloads/SWEX/MakingofSW.pdf