Which Netbook to get kind of depends on what your Usage scenario is going to be, and what features are important to you.
If you are going to do a lot of Typing on it for Work, You need to look for One with a 92-94% Keyboard which makes for a decent typing Experience.
Hp, Lenovo (New S10-2), Dell and Samsung from What I've seen have the best Keyboard's. Asus's and Acers Newer Models have decent ones, but Are not as good as the others.
If Battery life is a key concern then MSI Wind U110 has a claimed Battery life of 15hrs with the 9cell battery. Asus With the eeePC 1101HA Probably has the second best, with a claimed Life of over 11 Hours followed by the 1005HE at around 10hrs. Toshiba NB205-312 has been shown to have 9hrs of battery life in Tests. Samsung's Netbooks, also claim a batter life of 7 hours.
If Size and weight are key, then the Sony P is probably one of the best options. While a bit overpriced, Its Weight (700 Gms) combined with compact dimensions mean that it is a very compact Portable PC. While the battery life and specs are not that great, its a very compact and portable System, which I've personally used .
If Your Looking for a Reasonably powerful system, I'll suggest looking for one with Nvidia's Ion Chipset which will provide better Graphics performance on Notebooks. I Believe Lenovo, Samsung and a few others have announced Netbooks with it which will be shipping soon.
As such, Which one to get is definitely going to very much depend upon what features you price the most. Its a very individual choice, and I'll suggest you checking out reviews on the sites I'm mentioning below.
GottaBeMobile
Notebook Reviews
Liliputting
JK Mobile
For Getting the Best deals, I'll suggest checking out the following
LogicBuy - Which has regular deals and discount coupons.
Lenovo Outlet Store
Dells' Outlet Store
Hope this Helps