I am going to purchase a new turntable, it will have a solid hardwood plinth. It will come with  a OA2  gimbal tonearm, have a acrylic platter and a Ortofon 2M Blue cartridge. It comes with a felt mat, wondering if it would be fine to play records on just the acrylic with out the felt mat or should I use the felt mat provided
Try it both ways! You might also consider trying other mats.
I've always put the record right on the acrylic platter when the turntable has one.
free trial with no harm done as mentioned above

decide with your own ears
I would think that layer of felt would help to reduce rumble and vibration in the table.  What other materials are mats made of?  
If you do decide to try using just the platter sans mat don't forget to adjust your VTA. Personally I'd use the mat which should help minimize micro vibrations. 
My old Rega Planar 2 with upgraded acrylic platter sounds best to my ears with record direct on the platter, no mat at all but....ymmv.

Always avoid a mat whenever possible. 
flashcider, the goal is to keep the record from resonating and slipping on the platter. A record weight will stop the record from slipping but the problem with a hard platter surface is that it has a much different mechanical impedance than the record thus it will not keep the record from resonating. You want a mat that has a similar mechanical impedance to vinyl then it will serve to dampen any resonance in the vinyl. The Funk Firm Achromat get high marks for this and I would absolutely consider getting one of these. People love them. If my turntable did not come with an excellent mat I would definitely consider getting one!.
I have decided to get the Achromat 5mm in white. Have to order from across the pond cause retailers here in the states only carry black in 5mm. thanks for the heads up mijostyn, reached out to Arthur Kloubesserian at Funk Firm, very helpful.
While I do not believe personally you really need  a mat with the acrylic platter the 5mm Achromat is a great choice, had one and used it for years and yes I ordered from a dealer in England too.
Just remember though you are now adding 5mm to the height your record is sitting at relative to the stylus so you will need to adjust vta to suit
The Achromat is very nice. Let us know your impressions before/ after.  I still think no mat is best with acrylic, but your ears will let you know. Consider a clamp also. 
@flashcider - I place the record directly on the acrylic platter, BUT I also use a Thorens Stabilizer to prevent any slippage, which can occur on some albums, where the pressing is not quite PERFECT.


The benefits of the weight - a much "crisper" dynamic presentation

Regards - Steve
The Clearaudio CleverClamp is an inexpensive and effective option.