Surround speakers slightly in front OK?

Don't sweat it, it will sound fine. If at all possible, however, try aiming the speakers to a location behind you. This should help to overcome their less than textbook-style placement.

Merry Christmas!

-RW-

Balance is always a key issue, with any properly setup system. In the case of the location of the speakers, in relation to imaging and steering of the soundfield, you might find it a little less than enveloping, ideally. However, it would not sound bad, all things considered, just as if most of the sound-field is happening in front of you. Think of it as a more extended front sound stage, perceptively, than what a 3 speaker set up would do.
A concern I would have in placing any speaker in a room, would be how each speaker actually sounds in a given location! This is the most overlooked of considerations in speaker positioning by novices. You can easily have speakers and seating positions located where there are "holes" and nasty peaks in the sound (of course, with today's EQ tech, this is of much less concern, as it can be rectified electronically), if phase issues between speakers. The former is more often a culprit.
I would say, as long as you're able to get good overall sound from these speaker locations, then you would be "OK". with it, if no other options.
With anything, there are usually compromises to be had, short of a perfect ideal, obviously. yes, I think you'll still enjoy your system if you need to leave them there.
Have you considered ceiling mounting some speakers? Is that an option?

Scuby: If it sounds good to you then they are in the perfect spot!! Merry Christmas!