Asking an IT guy if Dell or HP or Lenovo makes the best laptop is like asking a redneck if Ford, Chevy, or Dodge make the best pickup truck. Pointless.
They all buy the same screens, hard drives, processors, memory, etc. The differences come in to play when you consider the amount of support and R&D used to develop the products. HP and Lenovo invest heavily in R&D - especially HP. Dell does not. Perhaps that is why Dell recently recalled 4.1 million batteries in 2006, because they had the nasty habit of catching on fire. Lenovo had this problem to a lesser extent. HP did not have the problem... even though HP bought batteries from the same manufacturer (HP spec'd out their batteries differently, and did not experience the problem).
Your best bet is to identify your needs & what is important to you (more mobile or more powerful? Bigger screen or lighter weight? WWAN integrated? etc). Then compare the models from each manufacturer that meet those requirements. For example: All manufacturers classify their business units into 4 categories... Ultra mobility (thin & light, 12.1" screen, ULV processors that lend themselves to incredible battery life, but sacrifice top end horse power); Standard/Mainstream (14" or 15" screens, big range of processor choices); Workstation class (big screens, awesome graphics capabilities, heavier but loaded; or Desktop replacement (may as well be a desktop, but it has every bell & whistle).
Once you identify the class of laptop you want, it narrows the field somewhat.
Oh, and whatever you buy will end up being the brand you recommend to everyone else as being the best.
And for all of you still reading who wish to know which pickup is the best: Nissan.