[Solved] No eth0 interface - Asus K53S

It was amazing the ease with which ubuntu 10.04 recognized the wifi card (during that period it was taken for granted that ethx interface would have been recognized) but after installing the ubuntu 10.04 one thing missing was the conspicuous Ethernet.
Few CMD line interrogation ascertained the same. Out of all the output the one given below specifies why

03:00.0 Network controller: Atheros Communications Inc. AR9285 Wireless Network Adapter (PCI-Express) (rev 01)
    Subsystem: Device 1a3b:2c37
    Flags: bus master, fast devsel, latency 0, IRQ 17
    Memory at ddc00000 (64-bit, non-prefetchable) [size=64K]
    Capabilities: [40] Power Management version 3
    Capabilities: [50] Message Signalled Interrupts: Mask- 64bit- Queue=0/0 Enable-
    Capabilities: [60] Express Legacy Endpoint, MSI 00
    Capabilities: [100] Advanced Error Reporting <?>
    Capabilities: [140] Virtual Channel <?>
    Capabilities: [160] Device Serial Number 12-14-24-ff-ff-17-15-00
    Capabilities: [170] Power Budgeting <?>
    Kernel driver in use: ath9k
    Kernel modules: ath9k

04:00.0 USB Controller: Device 1b21:1042 (prog-if 30)
    Subsystem: ASUSTeK Computer Inc. Device 1059
    Flags: bus master, fast devsel, latency 0, IRQ 19
    Memory at dd200000 (64-bit, non-prefetchable) [size=32K]
    Capabilities: [50] Message Signalled Interrupts: Mask- 64bit+ Queue=0/3 Enable-
    Capabilities: [68] MSI-X: Enable- Mask- TabSize=8
    Capabilities: [78] Power Management version 3
    Capabilities: [80] Express Legacy Endpoint, MSI 00
    Capabilities: [100] Virtual Channel <?>
    Kernel driver in use: xhci_hcd
    Kernel modules: xhci

05:00.0 Ethernet controller: Atheros Communications Device 1083 (rev c0)
    Subsystem: ASUSTeK Computer Inc. Device 1851
    Flags: bus master, fast devsel, latency 0, IRQ 5
    Memory at dc800000 (64-bit, non-prefetchable) [size=256K]
    I/O ports at 9000 [size=128]
    Capabilities: [40] Power Management version 3
    Capabilities: [48] Message Signalled Interrupts: Mask- 64bit+ Queue=0/0 Enable-
    Capabilities: [58] Express Endpoint, MSI 00
    Capabilities: [6c] Vital Product Data <?>
    Capabilities: [100] Advanced Error Reporting <?>
    Capabilities: [180] Device Serial Number ff-48-bf-10-4d-13-17-ff

The driver for the Atheros Ethernet can be found at http://media.cdn.ubuntu-de.org/forum/attachments/48/33/2666793-AR81Family-linux-v1.0.1.14.tar.gz
Followed the instructions at http://importgeek.wordpress.com/2012/05/10/atheros-onboard-network-card-not-detecting-on-ubuntu-10-04/

I cannot get my head around the matter that when
Ethernet controller: Realtek Semiconductor Co.
is available with drivers why in gods name would Asus select Atheros Ethernet.