If you are thinking about giving a kindle for Christmas your options are going to be limited. First, the Kindle Paperwhite (Bookwi.se Review) is backordered and current orders are not expected to ship until Dec 21st. Cutting it very close for Christmas. That is the expected shipping date for both the 3G and the wifi only models.
The basic $69 Kindle and the $139 Kindle with Keyboard are currently available and are both very good options. But when arguably your best kindle is three generations old, the Kindle with Keyboard, it shows how slow the evolution of the Kindle has been.
If you are thinking about the Kindle Tablets things are a bit better. The basic Kindle Fire ($159) and the Fire HD ($199) are read to ship right now. Of course both are competing against the Nexus 7 and the iPad Mini. Amazon wins with content against the Nexus 7 and with price against the iPad Mini. But it is not a slam dunk decision.
If you are waiting for the larger sized Fire HD 8.9 ($299) it will not ship until Dec 3 and the full reviews are not really out on it yet.
Another problem is that it is unlikely, because of low stock, that there will be any Black Friday deals. As far as I can tell, there has never been a Black Friday sale by Amazon on actual Kindles. There have been accessory sales, but not actual Kindle sales.
And unless Amazon is holding out, there do not appear to be any refurbished Kindles in the pipeline. That was my best hope when people asked me about what they should get for Christmas. Refurbished kindle are often a great deal. But at least right now, there are not any in stock.
For most people, I would recommend getting the basic Kindle. It is cheap, light, and currently available (and the one that I use. Although I picked it up on sale for $49 and it was refurbished.)