I am running a fairly old (1 year) installation  of archlinuxarm on a sheevaplug using an SD card. 
Can I just use  sudo pacman -Syu in the running system and expect this to work?
I can of course make a complete backup of the SD card so I'm not worrying about losing stuff.
Also I suspect that the internal flash kernel/system is even more out of date.
Is there a way to upgrade that from the SD card or should I just live with that as a fallback? 
Thanks to all the Arch and Arm gurus who work so hard on this stuff.
$this->bbcode_second_pass_code('', '$ uptime
 14:26:21 up 359 days, 15:44,  1 user,  load average: 0.00, 0.01, 0.05
robin@delilah ~:
$ df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/root              6641192   1161216   5142620  19% /
udev                     10240       116     10124   2% /dev
/dev/mmcblk0p1            9911      4374      5025  47% /boot
shm                     256412         0    256412   0% /dev/shm
tmpfs                   102400        12    102388   1% /tmp
tmpfs                     1024       304       720  30% /var/lock
tmpfs                     1024        44       980   5% /var/run
transientvarlog           5120       444      4676   9% /var/log
robin@delilah ~:
$ ls -alrt /boot
total 4299
drwx------  2 root root   12288 Dec  1  2010 lost+found
drwxr-xr-x 21 root root    4096 Mar  5  2011 ..
-rw-r--r--  1 root root 3111704 Apr 19  2011 uImage
-rw-r--r--  1 root root 1252354 Apr 19  2011 System.map26
drwxr-xr-x  3 root root    1024 Apr 19  2011 .
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