Updating records from a hash

I wrote into the http://railsforum.com yesterday and heard no reply on
a topic related to this.
When Rails programmers' deploy a 'naked' application to the web before
it has any user activity, it is VERY unattractive to search engines. I
thought it would be wise to embed one's 'keywords' into a few text
fields while generating 'placebo' records upon initial deployment.
I'd like to write a simple record generation routine that reads from a
KEYWORD hash and at various intervals substitutes these keywords with
a variable.
Could/would you point me in the right direction of getting started
with this.
Thank you,

I've thorough searched the web for any Rails code relating to this and
find none. To me, it's just another example of how Rails programmers'
are decoupled from the world of business.
I'd expire records based on time. These 'keyword' rich records would
be groomed out after reaching a certain age.
If I could see a chunck of code that read an input record (as you
describe in AWD, it would then run a 'block' that would run through a
'hash' and replaced words like REPLACEME with the next 'keyword' in
the hash.
I'm making great strides in developing the 'mother' of all web
applications, but am religated to find and copy code as I don't have
the intellect/experience to create my own. Obviously, I'm the business
side of this, too.
I am happy to share with the group, whatever I come up with.