Great price.
I just picked up the 9-speed Ultegra upgrade kit from Price Point. $329. Shifter, derailleur, chain and cassette. Great deal.
FAST shipping.
As for 10-speed vs. 9. I was certainly happy with 8 and raced on it for years, but good parts were getting hard to come by easily.
For the cassette spread that I run, the minute change in gear inches in the larger gears, make 10 a waste for me. For others, might be useful.
-Z