Considering how much flasks are giving now in Cataclysm, there's no way in hell that strength flask will only give 298 str, unless the big item squish went trough. They just haven't implemented all the numbers yet, so it's going to change with the next build soon enough.
Same with stats potions, just look at the current numbers vs. the numbers in beta.
The new ones WILL give much more, there's no doubt about it.