Are you going to be in the market for a Downtown Boston rental apartment in 2012?  Here is a quick snapshot of what happened in the Back Bay in 2011 from the available data in the MLS/Pin multiple listing service:  

On average expect the cost per square foot in 2011 was $3.75, with the average unit size right at 960 square feet.  Want to live in a full service building?  Here are three with their average cost per square foot:  Trinity Place $4.98-PSF, One Charles $4.02-PSF and The Mandarin came in at $6.85 PSF.  Keep in mind that the average unit in the Mandarin was over 2500 square feet so you would be paying north of $17,000...per month.