Google and Spreadsheets has changing the first page. With a new design and with a shiny menu, the user interface becomes more friendly.
For those that you didn't use already docs and spreadsheets I strongly recommend it, being very useful, specially when you need to access information from many places or to share them with other persons. Those applications are like those from Microsoft Office (Word and Excel), but with a fewer facilities regarding its design. Anyway I consider that it's good taking in consideration the access possibilities.
I use it from a couple of months and I didn't had any problems with it, but sometimes the connection may be lost, but with a single refresh you may solve the problem.