I used to be a pretty hardcore, uber priest if I may say so myself. Being a priest in WoW has a couple advantages, and a couple disadvantages. One of the big advantages is that you are a required element for almost any group. Sure, a druid could fill in (and do a fine job I might add), but when most groups are looking for a healer, they are looking for a priest. With that kind of popularity, you get a lot of tells asking you to join various instance parties. Now let me ask you which tell is more likely to garner you the healer your group needs...
[Leetganker] whispers: plz, plz plz join our gruop. need healz for wc. plzzzzzzzzzz
[Sindy] whispers: Heya! I was wondering if you felt like hitting WC tonight. We have a group all set, we just need a healer. We could even summon!
If I had a dollar for every time I got a tell very similar to the one Leetganker sent, I would have, um... let's just say I'd have a lot of dollars. How many times did I take Leetganker up on his offer? Never. I would never join a party with someone who talks like that. It gives the impression of being an immature moron, and whether Leetganker is an immature moron or not, I'll never know, as I am not grouping with the guy.
Sindy is much more friendly. She starts with a nice greeting...imagine that! Then she asks politely if I would like to go to Wailing Caverns tonight, lets me know the status of her group and even offers a summons. No typos, decent grammar and she comes off like someone who won't be an idiot once we get into the instance.