What to look for when purchasing a blender?

What to look for when purchasing a blender?

I currently don't have a blender after purchasing my own home and am
looking to get one for making smoothies primarily, but also for pureeing
for soups, etc.
I had a smoothie maker that I won as a prize; it was very obviously a
cheap unit. It barely handled frozen fruit and yogurt. Ice cream and
frozen fruit burned up the motor.
I am aware of the extreme "Home Improvement"-style "Binford-3000" Blendtec
blenders (also as proposed in this question) but they are extremely
expensive and I don't plan on incorporating cell phones or garden rakes
into my smoothies.
What should I look for to get a quality blender? I don't want to purchase
an inexpensive one three or four times in the next few years. I'd prefer
one that will last a long time and prove to be a good kitchen tool.
Edit:
In shopping for blenders, it seems that most seem to be between $30 and
$150. Obviously there are some questionably cheap ones and many that
exceed that range. So for the purposes of this question, assume that range
to be the budget.