I haven't written in a long time, but George R. R. Martin's A Storm of Swords inspired me to at least write something short about it as a review. No need to shield yourself from spoilers - I'm not going into specifics with this review, but you'll get more out of it if you've read the novel.
I came into this novel after enjoying the first three seasons of HBO's Game of Thrones. I read A Game of Thrones and A Clash of Kings, and felt generally underwhelmed with GRRM's writing. The plot was great, but the execution involved a lot of eating.
However, there seemed to have been a switch when it came to "ASoS", as fans seem to enjoy calling it. The same great plotting is there, but the writing is dramatically improved. I can't identify exactly what is better about this novel, but part of it is the characterization. The characters definitely have more identity to them than before, so that helped my enjoyment level.
There are still moments where I'm left wanting more from him, but overall there was enough here to warrant a five-star rating. I haven't started reading the other books (I need a break!), but I'd easily call this one the best.
As far as surprises go, there was only one plot point I knew going in (thanks to season 3 of the TV series); there were three others that caught me completely off-guard, and I was appropriately impressed.