Well that's good; next thing - if you're looking to make a girlfriend out of this HB, it might be worth adding her on your social networking sites..
I've recently found a statistic in Men's Health magazine that approximately 78% of women have a thorough scan of any potenial partners Facebook pages - for a deeper insight of what they are all about..
and now with Facebooks new settings that people can find things you've written of friends' walls etc - you're going to have to be careful with tasteless jokes, status updats, drunken / poor photos.
Just because she texted "ok

" isn't by any means a confirmation of a date in the future - just play to cards close you your chest and start to learn more about her..
I would assume you're not the call her instead of text type - so the next time to you text her, make it include something relating to something she said when you met / or said over IM / phone call etc. This is especially useful for picking up conversation into the next day(s)
A recent example of mine:
I was chatting to this lovely girl I met at a house warming party - easily a HB8, although there are some qualities I don't like about her - I still would like to "test the waters" as it were... I was talking to her on facebook about going to the gym - I do mostly weights and she is a cardio girl.. great.
HB: "hold on a few minutes - I need to stretch my legs! sore from running this morning"
Me: "Nothing quite like a good stretch after the gym!.. makes you feel so much more invigorated!"
HB: "you do it too??.. most of my friend think I'm crazy for streching so often each day?"
It carries on - just playful, flirty a bit provocative. But comes to an end when I decide to hit up the gym.. Shoulder Presses were calling.
Later the next day - I sent her a text. Me: "I was runnig to the gym this morning and ran past a crazy looking old dude wearing some retro tracksuit doing stretches on the sidewalk!!.. Reminded me of you - Having trouble imagining you in tight 70's running shorts though

"
And from the there the conversation picked up to a date later on in the week.
Simple, fluid, well executed.