I would not count on getting any profit from that. Off course the value of bitcoin is always a large factor on ROI,
8 Ghs Jalapeno generates currently about 0.006 bitcoins a day, so with current bitcoin value it would take around half a year (if taking electricity cost in calculation) to break even.
Difficulty is in the rise, and terahash machines are coming from multiple vendors during the beginning of next year, so more time it takes, more harder it will be to gain anything.
Once the next gen asics come out that can do 2-3TH of hashing power, your 8ghs will basically be worthless. If you want my opinion, sell it back now and look at the group buy section of the forums for people who are buying next gen asics and selling you shares. The price varies but you'll be looking at ~$15/Gh so your $800 can get you 53Ghs of hashing power in Q1/Q2 2014