Not really. It's a matter of placement, antennas, power, and drivers. You're going to get more power and performance out of an internal PCI/PCI-Express Wireless card than you would out of traditional USB dongles. It's nice to get a newer Wireless N adapter for performance, but it is also ideal to keep wireless adapters out of corners and also in a place where the signal is able to effectively get to a router. Also, getting a card with external antennas also tends to result in better performance/range over the internal ones.
