I have only owned this mower for a few weeks at this point and mowing twice has shown me that this is a really outstanding product!  Be sure to read the battery care portion of the manual so that you take care of handling and charging correctly.  It is a sealed AGM battery - way more powerful than something like a NiCd that many smaller powered tools use... more expensive as well.

I highly recommend this mower as it is easy to use, move, clean, everything!  Love it!!!

Update 09/2009:  Have found that I can get 3 or 4 mows out of one charge of the battery and it is still going strong.  I charge it after 2 or 3 for better battery care.  So a 2 day charge is easy to fit in at some point over a few weeks.  Still really love this product...