Good advice from all. If you go with the Nikon, then consider getting another Nikon as the backup so the all the lens, flash, etc and the rest will still fit. Ebay is a good place for used equipment at the basic level for a backup, it's where all my backup stuff comes from.

You may also want to consider a small monopod or tripod, a zoom at 300 may be a bit too much to handhold and still get sharp pictures.

You need the filter for the lens, be it skylight, polarizing, or UV. Think about it, one scratch will either ruin a filter costing less then $10, or a lens costing way more then that.