(I meant to paste a node changelog from Toad here to back up my point, but forgot to, and now I can't find it :/ )
Anyway : whether your node was "transient" or not, as determined by the transient=true/false setting in freenet.ini or freenet.conf, used to be important because transient nodes didn't get any requests.
However since bidirectional connections were introduced on both networks all nodes receive requests anyway, and nodes determine how "contactable" they are (along with estimating specialisation and other factors) to judge whether they should be sent a particular request. In other words the transient setting doesn't do anything now and for this reason is not even advertised to other nodes anymore.
So if you want to run a "permenant" node, you can achieve this just by making sure it is up as much as possible. It also helps considerably if you are able to receive incoming connections. To this end you should keep the ipAddress setting accurate, (if you have a dynamic IP use a dynamic DNS service e.g. http://dyndns.org
,) and make sure your listenPort is externally reachable e.g. by port forwarding from your broadband modem/router combo, opening the port in any personal firewalls etcetera.
You can still run a node behind a firewall without incoming connections if you really have to. It won't perform as well but it's still worthwhile.