Something is definitely odd here:
[rena@mercury:~ 500]
$ hostname
mercury
[rena@mercury:~ 501]
$ cat /etc/hosts
127.0.0.1 mercury localhost.localdomain localhost
::1 mercury localhost6.localdomain6 localhost6
#127.0.1.1 mercury.home mercury
#192.168.0.128 mercury.home mercury
#192.168.0.129 rei.home rei
192.168.1.210 mercury.home mercury
192.168.1.211 rei.home rei
192.168.1.212 konata.home konata

# The following lines are desirable for IPv6 capable hosts
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
[rena@mercury:~ 502]
$ host mercury
mercury has address 192.168.1.65
[rena@mercury:~ 504]
$ traceroute mercury
traceroute to mercury (127.0.0.1), 30 hops max, 60 byte packets
1 mercury (127.0.0.1) 0.034 ms 0.007 ms 0.007 ms
$ ifconfig
eth0 Link encap:Ethernet HWaddr 00:50:fc:9b:38:72
inet addr:192.168.1.210 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::250:fcff:fe9b:3872/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:7946 errors:0 dropped:0 overruns:0 frame:0
TX packets:7796 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:2581438 (2.5 MB) TX bytes:765379 (765.3 KB)
Interrupt:16 Base address:0xd400
...so am I 192.168.1.210 (as I wanted and as ifconfig claims), 192.168.1.65 (as host claims), or 127.0.0.1 (as traceroute claims)?