Could be an issue with not enough priming sugar. If your noticing some carbonation, then the yeast is alive and at 70-75F it should be fermenting whatever available sugars it can find.
Best thing to do would be swirling them up and giving them another week or so. If you notice no difference then you have two choices: either drink it as is, or carefully pour them into a keg and force carb. I had to do this once with a barleywine where the yeast had died off. I poured it into a 6.5gal bucket first, then used an autosiphon to rack it into a purged keg. The enemy here is oxidation, but if you do it carefully and use co2 when racking into the keg, you should be able to avoid it.