Last night I was in Amsterdam was in July for the NExt Web conference. In and out in the same day.
This time I took the opportunity to stay a bit longer, and looked for a couple of boutique hotels in the centrum / Jordaan area. I have to say that all this 'gracht's and old houses have a beautiful and peaceful feeling to them.
The odd thing is that they have no curtains over there in many houses, and you casn just peek into any house: beautiful interiors, old and modern.
Check Esme Vos' site for great small hotels:
http://www.weekendhotel.nl/hotels/Amsterdam/1/en
And the Thalys will take you there in a snap from London, Paris or Brussels.